Autoclaves

Midmark UltraClave M9: troubleshooting and error codes

The ServiceForge knowledge base holds 86 documented symptoms for the Midmark UltraClave M9, with 158 ranked causes, 158 diagnostic checks with test points and expected values, and 101 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

Instruments still wet after Drying Mode caution

Items remain wet at end of drying cycle; packs may burn during dry mode

Ranked causes

1. Improper operation or overload (common)
2. Sterilizer not level (occasional)
3. Chamber filter clogged (common)
4. Drying time insufficient (occasional)
5. Vent valve malfunction (occasional)
6. High-limit thermostat failure (rare)
7. Heating element defect (rare)
8. Temperature probe failure (rare)

First check

Verify load size and door position during dry mode

Test point: Chamber and door
Expected: Reduced load; door partially open during drying

3 more checks with pass and fail actions, 8 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Instruments still wet after Drying Mode or packs burning during Dry Mode caution

After drying cycle, instruments remain wet or packs show burn marks. Indicates improper drying temperature or time control.

Ranked causes

1. Sterilizer overloaded or improperly positioned (common)
2. Sterilizer not level (occasional)
3. Chamber filter clogged (common)
4. Incorrect drying time setting (occasional)
5. Heating element malfunction (occasional)
6. High-Limit Thermostat malfunction (occasional)
7. Vent valve malfunction (occasional)
8. Temperature probe malfunction (occasional)

First check

Check load size and door position during Dry Mode

Test point: Chamber and door
Expected: Load is not overloaded; door is partially open (not fully closed or fully opened)

3 more checks with pass and fail actions, 8 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Chamber pressure out of acceptable range

Error codes C633, C645, C647, C660–C675, C677 displayed; chamber pressure reading not within acceptable range for current cycle

Ranked causes

1. Pressure leaks in system (common)
2. Water level sensor defective (occasional)
3. Heating element failure (occasional)
4. Vent valve defective (occasional)
5. Air valve defective (occasional)
6. Chamber filters clogged (common)
7. Main PC board failure (rare)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Chamber temperature out of acceptable range

Error codes C533, C534, C544, C560–C575, C577 displayed; chamber temperature reading not within acceptable range for current cycle

Ranked causes

1. Sterilizer not level (occasional)
2. Pressure leaks present (occasional)
3. Chamber filter clogged (common)
4. Temperature sensor malfunction (occasional)
5. Water level sensor malfunction (occasional)
6. Heating element failure (occasional)
7. Main PC board failure (rare)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Display panel blank during power-up

Display panel shows no output and touchpad is unresponsive; unit does not respond to input during startup

Ranked causes

1. No power supply voltage (common)
2. Loose or damaged ribbon connector (occasional)
3. Fuse open or blown (occasional)
4. Display panel malfunction (occasional)
5. High-limit thermostat open circuit (rare)
6. Main PC board failure (rare)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Water level sensor did not detect full chamber

Error code C232 displayed; water not detected at proper level within 5 minutes of cycle start

Ranked causes

1. Low water in reservoir (common)
2. Chamber filter clogged (common)
3. Water level sensor malfunction (occasional)
4. Fill valve defective (occasional)
5. Air valve defective (occasional)
6. Main PC board failure (rare)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Display panel is blank

Touch pad does not work during power-up mode

Ranked causes

1. Supply voltage absent or low (common)
2. Loose or damaged wire connections (common)
3. Blown fuses (occasional)
4. Faulty display panel (occasional)
5. Main PC board failure (rare)

5 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Door switch contacts open during cycle

Error codes C326, C382, C383, or C384 displayed; door switch problem detected mid-cycle or door switch contacts remain closed after motor stops

Ranked causes

1. Door is open during cycle (common)
2. Door latch mechanism misaligned or defective (occasional)
3. Door motor or switch malfunction (occasional)
4. Improper operation - door opened during cycle (common)
5. Main PC board failure (rare)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

High-limit thermostat triggered during cycle

Error codes C980–C985 or C987 displayed; high-limit thermostat contacts opened during sterilization cycle

Ranked causes

1. Sterilizer overloaded (common)
2. Unit skips fill cycle (occasional)
3. Sterilizer not level (occasional)
4. Pressure leaks present (occasional)
5. High-limit thermostat malfunction (occasional)

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Printer does not generate printout

Optional printer attached to sterilizer fails to produce documentation output

Ranked causes

1. Printer paper empty or cartridge depleted (common)
2. Ribbon harness connection loose (common)
3. Printer electronics failure (occasional)
4. Main PC board printer interface fault (occasional)

First check

Inspect printer paper and ink cartridge

Test point: Printer paper tray and cartridge bay
Expected: Paper loaded and ink cartridge full

2 more checks with pass and fail actions, 4 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Biological test strips indicate items are not sterile patient safety

Biological indicators show sterilization was not effective; no error code displayed

Ranked causes

1. Sterilizer overloaded (common)
2. Incorrect or faulty test strips (common)
3. Incorrect trays installed (occasional)

First check

Verify load size and linen pack weight

Test point: Chamber
Expected: Load size appropriate for sterilizer capacity

2 more checks with pass and fail actions, 3 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fan does not run when temperature exceeds 130°F caution

Fan system inactive when chamber temperature is above 130°F or continues running below 100°F

Ranked causes

1. Fan thermostat malfunction (common)
2. Fan motor failure (common)
3. Main PC board defect (occasional)

First check

Test fan thermostat switch operation

Test point: Fan thermostat
Expected: Switch closes at 130°F and opens at 100°F

2 more checks with pass and fail actions, 3 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fan does not run when temperature exceeds 130°F or continues running when temperature drops below 100°F caution

Fan system fails to activate at proper temperature threshold or fails to stop at lower threshold, indicating temperature control or fan relay malfunction.

Ranked causes

1. Fan thermostat malfunction (common)
2. Fan malfunction (common)
3. Main PC Board malfunction (occasional)

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Printer does not generate print-out

Printer connected to sterilizer does not produce hardcopy output. Applicable to optional printer models.

Ranked causes

1. Printer paper exhausted or ink cartridge empty (common)
2. Printer hardware malfunction (occasional)
3. Main PC Board malfunction (occasional)

First check

Check printer paper supply and ink cartridge

Test point: Printer paper tray and cartridge compartment
Expected: Paper loaded, ink cartridge present and filled, ribbon connections secure

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Air valve not operating during I/O test

Air valve does not click open or close when energized during service diagnostics I/O test

Ranked causes

1. Air valve solenoid malfunction (common)
2. PC board output circuit malfunction (occasional)

First check

Press START button during air valve I/O test

Test point: Air valve solenoid connection
Expected: Audible click when valve opens and closes

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Calibration: Pressure zero, range, and temperature potentiometers high voltage

Adjustment procedure for pressure and temperature sensing potentiometers requiring coordinated calibration with test harness and multimeter verification.

Ranked causes

1. Potentiometer calibration drift or initial setup required (unknown)
2. Pressure display reads outside tolerance after calibration (unknown)

First check

Remove right hand side panel and open sterilizer door

Test point: Right hand side panel, sterilizer door
Expected: Panel removed, door open

11 more checks with pass and fail actions, 4 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Door does not open after test cycle completion patient safety

During M9/M11 door opening test, door pulse solenoid does not activate to open door automatically when test cycle finishes

Ranked causes

1. Door pulse solenoid malfunction (occasional)
2. Control PC board relay malfunction (occasional)

First check

Fill chamber with water and initiate any cycle

Test point: Chamber
Expected: Chamber fills with water; Sterilizing LED illuminates

4 more checks with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Door does not open at end of sterilizing cycle patient safety

After pressure drops to 0.7 psi, door motor does not rotate cam and latch lever fails to open door.

Ranked causes

1. Door motor fault or resistance out of range (common)
2. PC board relay not supplying voltage to door motor (occasional)

First check

Measure door motor resistance

Test point: Door motor terminals
Expected: 115 VAC: 6620 Ω ±20%; 230 VAC: 12,200 Ω ±20%, ±20%
Tools: Multimeter set to 20K ohms

1 more check with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Door motor not operating during I/O test

Door motor does not respond when energized during service diagnostics I/O test; door does not open

Ranked causes

1. Door motor malfunction (common)
2. PC board output circuit malfunction (occasional)

First check

Press START button during door motor I/O test with door closed

Test point: Door motor connection to latch mechanism
Expected: Door opens after approximately 15 seconds

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fan does not run or runs continuously caution

Fan motor fails to start or stops responding to thermostat control; may run continuously during consecutive cycles.

Ranked causes

1. Fan motor failure or no continuity (common)
2. Fan thermostat not switching contacts (common)

First check

Measure fan motor continuity

Test point: Fan terminals
Expected: Continuity (Ω) - reading shows resistance, not 0 or open
Tools: Multimeter set to ohms (Ω)

1 more check with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fan does not run when temperature exceeds 130° caution

Fan remains off when chamber or enclosure temperature rises above 130°

Ranked causes

1. Fan thermostat contacts not closing at 130° (common)
2. Primary fuses blown or faulty (occasional)

First check

Verify primary fuses are intact

Test point: Primary fuses (2) in power supply path
Expected: Both fuses unbroken; conducting
Tools: Multimeter or visual inspection

2 more checks with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fill valve not operating during I/O test patient safety

Fill valve does not open or allow water flow when energized during service diagnostics I/O test

Ranked causes

1. Fill valve solenoid malfunction (common)
2. PC board output circuit malfunction (occasional)

First check

Press START button during fill valve I/O test with door closed

Test point: Fill valve outlet to chamber
Expected: Water flows into chamber

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Heating element not operating during I/O test caution

Heating element does not energize or heat during service diagnostics I/O test

Ranked causes

1. Heating element failure or open circuit (common)
2. PC board output circuit malfunction (occasional)

First check

Press START button during heating element I/O test

Test point: Heating element terminals
Expected: Element heats for approximately 15 seconds then shuts off

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Instruments still wet after Dry Mode

Instruments remain wet at end of drying cycle

Ranked causes

1. Heating element not energizing properly during Dry Mode (common)
2. Temperature exceeds 240°F during drying (occasional)

First check

Verify heating element receives power during Dry Mode

Test point: Heating element terminals
Expected: Line VAC at pre-set intervals
Tools: Multimeter

1 more check with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Packs are burning during Dry Mode caution

Package contents char or burn during drying cycle

Ranked causes

1. Temperature control failure; heating element stays on too long (common)
2. Door closed during Dry Mode causing pressure buildup (occasional)

First check

Verify door is open before Dry Mode starts

Test point: Door switch status on display
Expected: Door open indicator displayed
Tools: Visual inspection, display panel

1 more check with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Power interruption detected

Unit displays error code C010 or C060 indicating power was interrupted or lost during operation

Ranked causes

1. Power cord connection loose or unplugged (common)
2. Sterilizer not on dedicated 15 amp circuit (occasional)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Vent valve not operating during I/O test

Vent valve does not click open or close when energized during service diagnostics I/O test

Ranked causes

1. Vent valve solenoid malfunction (common)
2. PC board output circuit malfunction (occasional)

First check

Press START button during vent valve I/O test

Test point: Vent valve solenoid connection
Expected: Audible click when valve opens and closes

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Air valve function and operation

Air valve opens during fill mode to allow water flow; closes during heat-up and sterilization modes; opens three times during heat-up to release chamber air

Ranked causes

1. Normal operation - valve controlled by PC board based on cycle mode (common)

First check

Verify air valve receives line voltage during fill mode

Test point: Air valve coil connector
Expected: Voltage present during fill mode, absent in other modes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Air valve malfunction during I/O test

Air valve does not click or respond when energized during I/O test in service diagnostics

Ranked causes

1. Air valve not opening or closing when energized (occasional)

First check

In I/O test, press START button to energize air valve

Test point: Air valve solenoid
Expected: Audible click when valve opens; click again when closed on second START

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Air valve solenoid coil open or faulty

Multimeter reading shows OL (open line) when testing air valve solenoid coil resistance, indicating the coil is open or has failed.

Ranked causes

1. Air valve solenoid coil open or shorted (common)

First check

Measure air valve solenoid coil resistance

Test point: Air valve terminals
Expected: Any reading other than OL
Tools: Multimeter set to M ohms (Ω)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Bubbles from bottom of reservoir

Bubbles observed coming from the bottom of the water reservoir during fill

Ranked causes

1. Fill valve contaminated or stuck (common)

First check

Observe water flow during fill mode for air bubbles

Test point: Reservoir bottom
Expected: Steady water flow without bubbles

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Bubbles rising from bottom of reservoir caution

Bubbles observed coming from the bottom of the water reservoir

Ranked causes

1. Fill valve malfunction or contamination (common)

First check

Observe for bubbles from reservoir bottom

Test point: Bottom of water reservoir
Expected: No bubbles during fill operation

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Chamber pressure reading incorrect

Service diagnostics I/O test chamber pressure display does not show 0.0 PSI with door open or shows incorrect pressure

Ranked causes

1. Pressure sensor malfunction or hose blockage (common)

First check

Verify chamber pressure during I/O test with door open

Test point: Pressure sensor hose connection at PC board
Expected: Display shows 0.0 PSI (0.0 kPa)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Chamber pressure reading incorrect in I/O test

I/O test display shows chamber pressure reading with door open when it should display 0.0 PSI (0.0 kPa)

Ranked causes

1. Pressure sensor disconnected, misaligned, or malfunctioning (occasional)

First check

In I/O test, open chamber door

Test point: Chamber door position
Expected: Door fully open

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Chamber temperature cannot be verified

Chamber temperature reading on I/O test display cannot be verified with independent thermometer; reading inconsistent

Ranked causes

1. Temperature sensor reading inaccurate or thermometer verification needed (unknown)

First check

Place external thermometer inside chamber

Test point: Chamber interior
Expected: Thermometer reading matches display reading within accuracy of meter

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Condensing tank assembly replacement

Removal and reinstallation of condensing tank assembly with water drain, fill tube connection, and sight/drain tube.

Ranked causes

1. Condensing tank damaged, cracked, or requires water drain/refill (occasional)

First check

Drain condensing tank water

Test point: Condensing tank drain
Expected: All water drained from tank

14 more checks with pass and fail actions, 3 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Display PC board button lamps do not illuminate

When buttons (UNWRAPPED, POUCHES, LIQUIDS, PACKS, START, STOP, ON/STANDBY) are pressed, their corresponding lamps fail to illuminate or stay illuminated

Ranked causes

1. Display PC board defective (common)

First check

Press and release each button in order

Test point: UNWRAPPED, POUCHES, LIQUIDS, PACKS, START, STOP, ON/STANDBY buttons
Expected: Corresponding lamp illuminates and stays illuminated

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Display PC board lamps do not illuminate sequentially

When power is connected while holding LIQUIDS and PACKS buttons, lamps on the display PC board fail to illuminate and extinguish in left-to-right sequence

Ranked causes

1. Display PC board defective (common)

First check

Observe display PC board lamps in sequence

Test point: Display PC board
Expected: Each lamp illuminates then extinguishes left to right

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Display PC board replacement

Removal and installation of display PC board with gasket and hardware from top cover.

Ranked causes

1. Display PC board damaged, cracked, or malfunctioning (occasional)

First check

Remove top cover

Test point: Top cover fasteners
Expected: Top cover removed and set aside safely

4 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Display PC board test and diagnostic check high voltage

Diagnostic procedure to test display PC board lamps, buttons, and displays for functionality verification.

Ranked causes

1. Display PC board lamps, buttons, or displays not functioning (occasional)

First check

Press and hold LIQUIDS and PACKS buttons simultaneously

Test point: LIQUIDS button, PACKS button (Figure 4-27)
Expected: Both buttons held down simultaneously

9 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Door gasket replacement

Removal and installation of door gasket and dam gasket to maintain pressure seal integrity.

Ranked causes

1. Door gasket worn, damaged, or leaking (common)

First check

Open sterilizer door

Test point: Sterilizer door
Expected: Door fully open

3 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Door motor system malfunction during I/O test

Door does not open after energizing door motor during I/O test; motor appears non-responsive

Ranked causes

1. Door motor not operating when energized (occasional)

First check

Ensure door is closed before starting test

Test point: Door position
Expected: Door fully closed and latched

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Door switch status incorrect in I/O test

I/O test display shows door switch status not matching actual door position; OPEN when closed or vice versa

Ranked causes

1. Door switch misaligned, stuck, or electrical connection loose (occasional)

First check

In I/O test, close door and observe door switch status on display

Test point: I/O test display door switch indicator
Expected: Display shows CLOSED when door is closed

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Door switch status not reflecting door position

Service diagnostics I/O test door switch status does not correctly show OPEN or CLOSED position

Ranked causes

1. Door switch malfunction or misalignment (common)

First check

Observe door switch status during I/O test while opening and closing door

Test point: Door switch sensor connection
Expected: Status shows OPEN when door open, CLOSED when door closed

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Error codes displayed in recall errors test

Service diagnostics recall errors function displays error codes indicating previous faults or diagnostic findings

Ranked causes

1. System recorded error conditions during previous operation (common)

First check

In service diagnostics, select Recall Errors from test menu

Test point: Display screen
Expected: Last five error codes displayed with 1=most recent, 5=oldest

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fan continues to run after temperature drops below 100° caution

Fan does not stop even when internal temperature falls below 100°

Ranked causes

1. Fan thermostat contacts not opening (common)

First check

Allow sterilizer to cool and verify fan stops

Test point: Fan thermostat temperature reset point
Expected: Contacts open and fan stops at approximately 100°F
Tools: Thermometer

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fill or vent valve solenoid coil open

Multimeter reading shows OL (open line) when testing fill or vent valve solenoid coil resistance, indicating the coil has failed.

Ranked causes

1. Fill or vent valve solenoid coil open or faulty (common)

First check

Measure fill or vent valve solenoid coil resistance

Test point: Valve terminals
Expected: Any reading other than OL
Tools: Multimeter set to M ohms (Ω)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fill valve malfunction during I/O test

Fill valve does not open or water does not flow when energized during I/O test; no water enters chamber

Ranked causes

1. Fill valve stuck closed or obstructed (occasional)

First check

Ensure door switch is tripped (close door or manually trip)

Test point: Door switch
Expected: Switch activated to enable fill valve operation

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fill valve solenoid coil open or faulty

Ohmmeter reading shows OL (open circuit) when testing fill valve solenoid coil resistance with meter set to M ohms scale

Ranked causes

1. Solenoid coil open or burned out (common)

First check

Measure fill valve solenoid coil resistance

Test point: Fill valve terminals
Expected: Any reading other than OL
Tools: Digital multimeter set to M ohms (Ω) scale

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Filter replacement

Removal and installation of sterilizer filter into pressure vessel with rubber hammer tapping.

Ranked causes

1. Filter clogged, contaminated, or requires replacement (common)

First check

Remove old filter from pressure vessel

Test point: Filter (1), pressure vessel (2) (Figure 4-21)
Expected: Old filter removed

1 more check with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Foreign characters displayed on panel

Display panel shows corrupted or foreign characters while touchpad functions normally and continuous beeping occurs

Ranked causes

1. Display ribbon connector loose or damaged (common)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Foreign characters on display panel

Garbled text appears on display; touchpad works and unit beeps continuously

Ranked causes

1. Loose or damaged display PC board ribbon connector (common)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fuse blown or open

Unit does not power on or specific circuits non-functional; fuse reads open with multimeter

Ranked causes

1. Fuse F1 or F2 open circuit (common)

First check

Measure fuse continuity with multimeter set to 200 Ω

Test point: Fuse F1 or F2 ends
Expected: Less than 5 Ω resistance, < 5 Ω
Tools: Multimeter set to 200 Ω

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Fuse failure caution

One or both fuses open or not conducting

Ranked causes

1. Blown fuse due to overcurrent or component failure (common)

First check

Set multimeter to ohms and measure fuse continuity

Test point: Each end of fuse
Expected: less than 5 Ω, less than 5
Tools: Multimeter set to 200 Ω range

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Heating element malfunction during I/O test high voltage

Heating element does not heat or does not shut off as expected during I/O test

Ranked causes

1. Heating element not energizing or not shutting off properly (occasional)

First check

In I/O test, press START to energize heating element

Test point: Heating element connections
Expected: Element heats for approximately 15 seconds then automatically shuts off

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Heating element not heating or resistance out of range

Ohmmeter reading of heating element resistance falls outside acceptable range when measured at heating element terminals

Ranked causes

1. Heating element open, shorted, or resistive element degraded (common)

First check

Measure heating element resistance

Test point: Heating element terminals
Expected: 115 VAC: 9.0 to 11.0 ohms; 230 VAC: 34.0 to 42.0 ohms
Tools: Digital multimeter set to 200 ohms (Ω) scale

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Heating element resistance out of range high voltage

Multimeter resistance measurement of heating element is outside acceptable range, indicating element is degraded or failed.

Ranked causes

1. Heating element burned out or shorted (common)

First check

Measure heating element resistance

Test point: Heating element terminals
Expected: 115 VAC: 9.0 to 11.0 ohms; 230 VAC: 34.0 to 42.0 ohms ohms (115 VAC) or 34, 115 VAC ±2.0 ohms; 230 VAC ±8.0 ohms
Tools: Multimeter set to 200 ohms (Ω)

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

High-limit thermostat showing open status caution

Service diagnostics I/O test displays high-limit thermostat status as OPEN instead of CLOSED

Ranked causes

1. High-limit thermostat malfunction or unit has overheated (common)

First check

Monitor high-limit thermostat status during I/O test

Test point: Thermostat output to PC board
Expected: Status should always be CLOSED

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

High-limit thermostat status abnormal caution

I/O test display shows high-limit thermostat status as OPEN instead of normal CLOSED; indicates overheating or malfunction

Ranked causes

1. High-limit thermostat malfunctioning or tripped from overheating (occasional)

First check

In I/O test, observe high-limit thermostat status on display

Test point: I/O test display
Expected: High-limit thermostat status: CLOSED

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Keytest button malfunction

Button on touch pad does not register or beep when pressed during keytest in service diagnostics

Ranked causes

1. Touch pad button stuck, non-responsive, or electrical connection loose (occasional)

First check

In keytest, press START button when highlighted

Test point: START button on touch pad
Expected: Audible beep and test advances to next button

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

More symptoms

Leakage from system fittings
Loose fittings causing leaks
PC board not powering unit or fuses faulty
Pressure and temperature/time displays not functioning
Pressure relief valve does not close or sticks open
Pressure relief valve does not re-seat properly
Pressure relief valve does not vent steam
Pressure relief valve leaks or will not close
Pressure relief valve replacement
Service diagnostics access required
Steam exhausting from condensing coil during sterilization
Steam leaking from pressure sensor hose connection
Stop button pressed during cycle
Temperature sensor resistance out of acceptable range
Temperature sensor resistance out of range
Touch pad button not responding
Touch pad buttons not responding
Unit overheating during drying cycle
Vent valve malfunction during I/O test
Vent valve solenoid coil open or faulty
Water leaking around door
Water leaking from condensing coil
Water level sensor status incorrect
Water level sensor status incorrect in I/O test
Water or steam leakage under sterilizer back
Water or steam leaking from back of unit

26 more symptoms with ranked causes and checks are in ServiceForge. Connect ServiceForge to your AI

Error codes

Code	Meaning	Trigger	Severity
`C010`	Power interruption - General System	Power loss or interruption detected during operation	warning
`C010`	Power-Up Mode error	Detected during Power-Up Mode initialization	error
`C060`	Power interruption - General System	Power loss detected during operation	warning
`C060`	Power-Up Mode error	Detected during Power-Up Mode initialization	error
`C099`	Factory test code	Generated during factory testing	info
`C099`	Power-Up Mode error	Detected during Power-Up Mode initialization	error
`C102`	Fill Mode error	Water level sensor or fill valve malfunction during fill cycle	error
`C102`	Stop button pressed during cycle	STOP button activated during active sterilization cycle	warning
`C103`	Heat-Up Mode error	Detected during Heat-Up Mode temperature ramp	error
`C103`	Stop button pressed during cycle	STOP button activated during active sterilization cycle	warning
`C104`	Stop button pressed during cycle	STOP button activated during active sterilization cycle	warning
`C104`	Sterilization Mode error	Detected during Sterilization Mode holding phase	error
`C105`	Stop button pressed during cycle	STOP button activated during active sterilization cycle	warning
`C105`	Error in Vent Mode system	Vent Mode operation failure	error
`C106`	Error in Door Motor System	Door motor or door switch malfunction	error
`C106`	Stop button pressed during cycle	STOP button activated during active sterilization cycle	warning
`C232`	Water level sensor did not detect full chamber	Water level not detected within 5 minutes of cycle start	error
`C326`	Error in Door Motor System	Door motor operation failure	error
`C326`	Door switch contact problem	PC board detected open door switch contacts during cycle or door switch contacts remained closed after motor stopped	error
`C326`	Door switch open during cycle or stuck closed after motor shutdown	PC board detected open door switch or contacts remained closed after motor shut off	error
`C382`	Door switch contact problem	PC board detected open door switch contacts during cycle or door switch contacts remained closed after motor stopped	error
`C382`	Fill or Heat-Up mode air valve error	Air valve fails to open or close as expected	error
`C382`	Door switch open during cycle or stuck closed after motor shutdown	Door switch contacts open or remain closed after motor shut off	error
`C383`	Door switch contact problem	PC board detected open door switch contacts during cycle or door switch contacts remained closed after motor stopped	error
`C383`	Heat-Up Mode - Vent valve malfunction	Vent valve fails during Heat-Up Mode	error
`C383`	Door switch open during cycle or stuck closed after motor shutdown	Door switch contacts open or remain closed after motor shut off	error
`C384`	Door switch open during cycle or stuck closed after motor shutdown	Door switch contacts open or remain closed after motor shut off	error
`C384`	Sterilization Mode - Vent valve malfunction	Vent valve fails during Sterilization Mode	error
`C384`	Door switch contact problem	PC board detected open door switch contacts during cycle or door switch contacts remained closed after motor stopped	error
`C533`	Heat-Up Mode - Pressure sensor error	Pressure sensor malfunction during Heat-Up Mode	error
`C533`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C534`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C534`	Sterilization Mode temperature error	Temperature deviates from sterilization setpoint during cycle	error
`C544`	Sterilization Mode temperature high error	Chamber temperature exceeds safe maximum during sterilization	error
`C544`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C560`	Chamber temperature out of range with power interruption after error display	Temperature reading out of range; power interruption occurred after error was displayed	error
`C561`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C562`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C562`	Fill Mode pressure error	Pressure detected in chamber during fill phase	error
`C563`	Heat-Up Mode - Fill valve malfunction	Fill valve fails to close or solenoid de-energizes during Heat-Up Mode	error
`C563`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C564`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C564`	Sterilization Mode - Fill valve malfunction	Fill valve fails to close or solenoid de-energizes during Sterilization Mode	error
`C565`	Error in Vent Mode system	Vent Mode operation failure	error
`C567`	Error in Drying Mode system	Drying Mode operation failure	error
`C567`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C570`	Chamber temperature out of range with power interruption after error display	Temperature reading out of range; power interruption occurred after error was displayed	error
`C571`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C572`	Fill Mode - Air valve malfunction	Air valve fails to operate during Fill Mode	error
`C572`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C573`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C573`	Heat-Up Mode vent valve error	Vent valve malfunction during heat-up phase	error
`C574`	Sterilization Mode - Air valve malfunction	Air valve fails to remain closed during Sterilization Mode	error
`C574`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C575`	Error in Vent Mode system	Vent Mode operation failure	error
`C575`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C577`	Chamber temperature outside acceptable range	Temperature reading not within acceptable range for current cycle	error
`C577`	Error in Drying Mode system	Drying Mode operation failure	error
`C633`	Low chamber pressure error	Chamber pressure reading below acceptable range for current cycle	error
`C633`	Heat-Up Mode - Temperature sensor error	Temperature sensor malfunction during Heat-Up Mode	error
`C645`	Error in Vent Mode system	Vent Mode operation failure	error
`C645`	High chamber pressure error	Chamber pressure reading above acceptable range for current cycle	error
`C647`	High chamber pressure error	Chamber pressure reading above acceptable range for current cycle	error
`C647`	Error in Drying Mode system	Drying Mode operation failure	error
`C660`	Chamber pressure outside acceptable range; power interruption after error	Pressure out of range and power loss occurred after error display	error
`C661`	Hardware pressure sensor error	Pressure sensor hardware malfunction detected	error
`C662`	Fill Mode - Door switch open during cycle	Door switch opens unexpectedly during Fill Mode	error
`C662`	Hardware pressure sensor error	Pressure sensor hardware malfunction detected	error
`C663`	Hardware pressure sensor error	Pressure sensor hardware malfunction detected	error
`C663`	Heat-Up Mode - Door switch open during cycle	Door switch opens unexpectedly during Heat-Up Mode	error
`C664`	Sterilization Mode - Door switch open during cycle	Door switch opens unexpectedly during Sterilization Mode	error
`C664`	Sterilization Mode temperature sensor error	Temperature sensor signal loss during sterilization	error
`C665`	Error in Vent Mode system	Vent Mode operation failure	error
`C665`	Hardware pressure sensor error	Pressure sensor hardware malfunction detected	error
`C667`	Hardware pressure sensor error	Pressure sensor hardware malfunction detected	error
`C667`	Error in Drying Mode system	Drying Mode operation failure	error
`C670`	Chamber pressure outside acceptable range; power interruption after error	Pressure out of range and power loss occurred after error display	error
`C671`	High chamber pressure error	Chamber pressure reading above acceptable range for current cycle	error
`C672`	Fill Mode - High-Limit Thermostat fault	High-Limit Thermostat opens unexpectedly during Fill Mode	error
`C672`	Low-to-medium pressure error	Pressure reading below acceptable range during specific cycle phase	error
`C673`	Heat-Up Mode - High-Limit Thermostat fault	High-Limit Thermostat opens unexpectedly during Heat-Up Mode	error
`C673`	Low-to-medium pressure error	Pressure reading below acceptable range during specific cycle phase	error
`C674`	Sterilization Mode pressure sensor error	Pressure sensor signal loss during sterilization	error
`C674`	Sterilization Mode - High-Limit Thermostat fault	High-Limit Thermostat opens unexpectedly during Sterilization Mode	error
`C675`	High chamber pressure error	Chamber pressure reading above acceptable range for current cycle	error
`C675`	Error in Vent Mode system	Vent Mode operation failure	error
`C677`	High chamber pressure error	Chamber pressure reading above acceptable range for current cycle	error
`C677`	Error in Drying Mode system	Drying Mode operation failure	error
`C980`	High-limit thermostat opened during cycle	High-limit thermostat contacts opened during sterilization cycle	error
`C981`	High-limit thermostat opened during cycle	High-limit thermostat contacts opened during sterilization cycle	error
`C982`	Fill Mode - Main PC Board fault	Main PC Board malfunction detected during Fill Mode	critical
`C982`	Fill Mode door switch error	Door opened or door switch fault during fill cycle	error
`C982`	High-limit thermostat opened during cycle	High-limit thermostat contacts opened during sterilization cycle	error
`C983`	Heat-Up Mode - Main PC Board fault	Main PC Board malfunction detected during Heat-Up Mode	critical
`C983`	High-limit thermostat opened during cycle	High-limit thermostat contacts opened during sterilization cycle	error
`C984`	High-limit thermostat opened during cycle	High-limit thermostat contacts opened during sterilization cycle	error
`C984`	Sterilization Mode - Main PC Board fault	Main PC Board malfunction detected during Sterilization Mode	critical
`C985`	Error in Vent Mode system	Vent Mode operation failure	error
`C985`	High-limit thermostat opened during cycle	High-limit thermostat contacts opened during sterilization cycle	error
`C987`	High-limit thermostat opened during cycle	High-limit thermostat contacts opened during sterilization cycle	error
`C987`	Error in Drying Mode system	Drying Mode operation failure	error

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ServiceForge knowledge base record. Field-unverified unless technicians confirmed it. A teaching summary of the record, not a service manual. Export 2026-10-14.