Respiratory support systems · Infant Flow family

BD Infant Flow SiPAP: troubleshooting and error codes

The ServiceForge knowledge base holds 54 documented symptoms for the BD Infant Flow SiPAP, with 63 ranked causes, 90 diagnostic checks with test points and expected values, and 68 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

Blender whistle caution

Audible alarm from blender unit. Verify inlet gas pressures, check watertraps and filters.

Ranked causes

1. Watertrap blocked, full or leaking (common)
2. Filters blocked (common)
3. Loss of wall pressure or imbalance in gas supply (occasional)

First check

Inspect watertrap for blockage or fullness

Test point: Blender inlet watertrap
Expected: Clear, not full or leaking

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

Unit does not start or fails self-test

Screen remains black and warning bar stays on after power switch is set to ON.

Ranked causes

1. Program memory fault (occasional)
2. Power supply not connected (common)
3. Emergency battery voltage low (occasional)

First check

Verify mains power connection

Test point: AC power inlet
Expected: Mains power present and secure

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

Flow meter fault caution

No flow indications or flow cannot be adjusted. Check flow meter knobs for damage or occlusion or kinks in flow meter tubes.

Ranked causes

1. Flow meter knobs damaged or occluded (common)
2. Kinks or blockage in flow meter tubes (common)

First check

Visually inspect flow meter knobs

Test point: Flow meter control knobs
Expected: Intact, freely movable, no obstruction

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

Oxygen sensor calibration error caution

Error code displayed. Oxygen sensor incorrectly calibrated, damaged or depleted.

Ranked causes

1. Oxygen sensor incorrectly calibrated, damaged or depleted (common)
2. Oxygen sensor end of life or malfunction (occasional)

First check

Perform oxygen sensor calibration

Test point: Oxygen sensor calibration port
Expected: Calibration completes successfully

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

Power-on self-test fails

Screen remains darkened and warning bar remains on during power-up check

Ranked causes

1. Power Supply not connected (common)
2. Battery voltage low (common)

First check

Verify power supply connection

Test point: Power cord to AC outlet
Expected: Power cord connected to AC power

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

Pressure reading low during nCPAP operation patient safety

Measured pressure on screen is below 4-5 cmH2O during nCPAP mode when prongs are occluded

Ranked causes

1. Circuit leak (common)
2. Circuit blockage (common)

First check

Verify flow meter setting and measured pressure with prongs occluded

Test point: nCPAP/Pres Low flow meter and pressure display
Expected: 5 ±1 cmH2O at 8-9 lpm (depending on circuit type)

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

Unit fails Power-On Check patient safety

Screen remains darkened and warning bar remains on after power-up; unit does not display Power-up screen

Ranked causes

1. Power supply not connected (common)
2. Battery voltage low (occasional)

First check

Verify AC power connection

Test point: Power cord and AC outlet
Expected: Power cord connected to AC outlet; outlet powered

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

Apnea detected patient safety

Breath rate zero for duration exceeding breath rate timeout. Intermittent high level audible alarm, Warning Bar flashes, breath rate digital display flashes, breath rate icon flashes.

Ranked causes

1. Patient breathing ceased or not detected by trigger module (common)

First check

Monitor breath rate display and patient breathing

Test point: Breath rate digital display and patient
Expected: Breath rate > 0 and patient breathing detected

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

Battery fault caution

Intermittent high level audible alarm, Warning Bar flashes intermittently, battery status indicator flashes, screen displays flashing error code.

Ranked causes

1. Battery disconnected or failing to take or hold charge (common)

First check

Check battery connection and status indicator

Test point: Battery status indicator and physical battery connection
Expected: Steady indicator, secure connection

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

Battery fault alarm

Intermittent high level audible alarm, warning bar flashes intermittently, battery status indicator flashes, screen displays flashing fault code (E number).

Ranked causes

1. Battery disconnected or failing to take or hold charge (rare)

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

BiPhasic/BiPhasic Tr mode fails to operate as set patient safety

Intermittent high level audible alarm, Warning Bar flashes intermittently, nCPAP Pres high on time display flashes, screen displays flashing error code. Cannot be silenced.

Ranked causes

1. BiPhasic or BiPhasic Tr mode software/hardware failure (rare)

First check

Note error code on screen

Test point: Screen error code display
Expected: Specific error code per Chapter 9

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

BiPhasic/BiPhasic Tr mode fails to operate as set patient safety

Intermittent high level audible alarm, warning bar flashes intermittently, NCPAP Pres high on time display flashes, screen displays flashing fault code (E number).

Ranked causes

1. BiPhasic mode operation failure detected (rare)

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

Blender whistle alarm caution

Audible alarm from blender.

Ranked causes

1. Water trap blocked, full or leaking; filters blocked; loss of wall pressure; imbalance of wall gas supply (occasional)

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

Calibration: Alarms test setup and verification patient safety

Verify alarm system operation at specified unit settings (nCPAP mode, 8-9 lpm, 5 cmH2O, 30% O2)

Ranked causes

1. Alarm system calibration and reset required (unknown)

First check

Unit mode configuration

Test point: Unit mode selector
Expected: nCPAP Mode

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

Calibration: Blender oxygen delivery accuracy patient safety

Verify FiO2 output at blender control settings (21%, 30%, 60%, 90%, 100%) matches displayed values on SiPAP unit and external analyzer

Ranked causes

1. Blender oxygen concentration calibration required (unknown)

First check

SiPAP FiO2 display at 21% blender setting

Test point: SiPAP display screen
Expected: 21% (±3%), ±3%
Tools: Calibrated oxygen analyzer

9 more checks with pass and fail actions, 5 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Calibration: Oxygen sensor patient safety

Initial O2 sensor calibration required before unit setup in patient mode. Performed during power-up startup sequence.

Ranked causes

1. Unit powered on without O2 sensor calibration (common)

First check

Power switch set to ON position

Test point: Back panel power switch
Expected: Switch in ON position

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

Calibration: Power-on check patient safety

Verify unit performs automatic self-checks on power-up including ROM, I/O, alarms, pressure sensor, and dump valve before clinical use

Ranked causes

1. Incomplete power-on self-test (unknown)

First check

Flash ROM test

Test point: Internal memory
Expected: Test passes automatically during power-on

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

Case/cover removal procedure caution

Step-by-step instructions for removing the plastic case/cover from the Infant Flow SiPAP unit to access internal components for service

Ranked causes

1. Case/cover must be removed for internal service (common)

First check

Locate and remove eight screws on rear panel

Test point: Rear panel
Expected: All eight screws removed

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

CPAP returns to wrong level after prong occlusion release patient safety

Pressure display shows 0-2 cmH2O when occlusion is removed, but does not return to 5 cmH2O when re-occluded or interface remains occluded

Ranked causes

1. Interface circuit occlusion not relieved (common)

First check

Remove occlusion from prongs and measure pressure

Test point: Pressure display with nasal prongs open
Expected: 0-2 cmH2O

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

Discharged battery

Battery voltage too low to power circuits; screen changes to Flat Battery screen

Ranked causes

1. Battery depleted (common)

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

Electrical fault high voltage

External power light does not match screen icon.

Ranked causes

1. External power indicator mismatch with display (rare)

First check

Verify power indicator status

Test point: External power light and screen power icon
Expected: Both indicate same power status (on/off)

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

Electrical fault caution

External power light does not match screen icon. Contact CareFusion SiPAP technical support.

Ranked causes

1. Power indicator light/software mismatch or internal electrical failure (rare)

First check

Compare external power indicator light with screen display

Test point: Power indicator LED and screen power status icon
Expected: Light and icon state match (both on or both off)

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

External power disconnected caution

Intermittent high level audible alarm, Warning Bar flashes intermittently, battery status indicator and power indicator alternately flash.

Ranked causes

1. External power supply disconnected from unit (common)

First check

Verify AC power connection

Test point: Power indicator and physical AC connector
Expected: Power indicator lit, AC power cord seated

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

External power disconnected alarm

Intermittent high level audible alarm, warning bar flashes intermittently, battery status indicator and power indicator alternately flash.

Ranked causes

1. AC power supply disconnected from unit (common)

First check

Verify power cord connection

Test point: AC power input connector
Expected: Power cord firmly connected and wall outlet powered

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

Fault lockout patient safety

Software detects fault preventing correct operation; Fault Lockout screen displayed with fault code numbers

Ranked causes

1. Detectable software fault (unknown)

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

Flowmeter fault caution

No flow indications or flow cannot be adjusted.

Ranked causes

1. Flowmeter malfunction (rare)

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

High BiPhasic/BiPhasic Tr MAP pressure patient safety

High MAP pressure display flashes, Warning Bar flashes, intermittent high level audible alarm, Alarm Button flashes, digital high MAP pressure limit highlighted.

Ranked causes

1. Mean airway pressure exceeds 3 cmH2O above set point for 15 seconds (common)

First check

Monitor high MAP pressure display

Test point: BiPhasic/BiPhasic Tr MAP pressure reading
Expected: ≤ 3 cmH2O above set point

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

High BiPhasic/BiPhasic Tr pressure alarm patient safety

Intermittent high level audible alarm, warning bar flashes, high MAP pressure display flashes, digital high MAP pressure limit highlighted, alarm button flashes.

Ranked causes

1. Mean airway pressure exceeds 3 cmH2O above set point (unknown)

First check

Verify MAP setting and actual pressure

Test point: High MAP pressure display
Expected: Within 3 cmH2O above set point

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

High nCPAP pressure patient safety

Pressure display flashes, Warning Bar flashes, intermittent high level audible alarm, Alarm Button flashes, digital pressure high limit highlighted.

Ranked causes

1. Pressure exceeds 3 cmH2O above set point for 15 seconds (common)

First check

Monitor pressure display

Test point: nCPAP pressure reading
Expected: ≤ 3 cmH2O above set point

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

High oxygen concentration patient safety

FiO2 display flashes, Warning Bar flashes, intermittent high level audible alarm, Alarm Button flashes, digital O2 alarm high limit highlighted, Error Code appears.

Ranked causes

1. FiO2 exceeds 5% above set point for 15 seconds or exceeds 104% for 15 seconds (common)

First check

Verify FiO2 level on display

Test point: FiO2 digital display
Expected: ≤ 5% above set point or ≤ 104%

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

Leak check: Gas connections caution

Test for leaks at all pipe connections, valves and fittings during pressurized gas flow

Ranked causes

1. Leaking tubing or connections (common)

First check

Ensure whistle sounds during gas connection

Test point: Device audio output
Expected: Whistle audible

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

Loss of Power

Loss of AC power and battery power together. Screen may go blank.

Ranked causes

1. Both AC power and battery are depleted or disconnected (rare)

First check

Verify AC power connection and battery charge

Test point: AC power adapter and battery
Expected: AC power connected and/or battery above 11.10 V

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

Low battery charge caution

Battery status indicator changes from green to red. No audible alarm.

Ranked causes

1. Battery charge below 40% (common)

First check

Check battery status indicator color

Test point: Battery status indicator on display
Expected: Green (charged above 40%)

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

Low battery charge alarm

Battery status indicator changes from gray to red.

Ranked causes

1. Battery charge below 40% (common)

First check

Observe battery status indicator color

Test point: Battery status indicator
Expected: Gray (normal) or red (low charge)

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

Low battery voltage caution

Intermittent medium level audible alarm, Warning Bar flashes intermittently, battery status indicator flashes, unit starts controlled shut down.

Ranked causes

1. Battery voltage drops below 11.10 V for 5 seconds (common)

First check

Verify battery voltage

Test point: Battery voltage measurement
Expected: ≥ 11.10 V

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

Low battery voltage alarm

Intermittent medium level audible alarm, warning bar flashes intermittently, battery status indicator flashes, unit starts controlled shutdown at set limit.

Ranked causes

1. Battery voltage drops below 10 V (common)

First check

Monitor battery voltage

Test point: Battery status indicator and display
Expected: Above 10 V

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

Low breath rate alarm patient safety

Intermittent high level audible alarm, warning bar flashes, breath rate digital display flashes, breath rate icon flashes. In BiPhasic models with monitored NCPAP+Apnea, a single sigh is given. In BiPhasic Tr Mode backup sighs at set rate are given.

Ranked causes

1. Patient breath rate drops to zero for timeout period (occasional)

First check

Observe breath rate display

Test point: Breath rate digital display and icon
Expected: Breath rate > 0 and above timeout threshold

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

Low nCPAP pressure patient safety

Pressure display flashes, Warning Bar flashes, intermittent high level audible alarm, Alarm Button flashes, digital pressure low limit highlighted.

Ranked causes

1. Pressure drops 2 cmH2O below set point for 15 seconds or falls below 1 cmH2O (common)

First check

Monitor pressure display

Test point: nCPAP pressure reading
Expected: ≥ 2 cmH2O below set point and ≥ 1 cmH2O

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

Low oxygen concentration patient safety

FiO2 display flashes, Warning Bar flashes, intermittent high level audible alarm, Alarm Button flashes, digital O2 alarm low limit highlighted.

Ranked causes

1. FiO2 drops 5% below set point for 15 seconds or falls below 20% for 15 seconds (common)

First check

Verify FiO2 level on display

Test point: FiO2 digital display
Expected: ≥ 5% below set point and ≥ 20%

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

Low pressure alarm patient safety

Intermittent high level audible alarm, warning bar flashes, pressure display flashes, digital pressure low limit highlighted, alarm button flashes.

Ranked causes

1. Pressure below alarm threshold (unknown)

First check

Verify actual patient pressure

Test point: Pressure display
Expected: Within 2 cmH2O above set point

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

Minimum oxygen concentration too low patient safety

FiO2 display flashes, Warning Bar flashes, intermittent high level audible alarm, Alarm Button flashes, Error Code appears, digital O2 alarm low limit highlighted.

Ranked causes

1. FiO2 level below 18% (common)

First check

Verify FiO2 level on display

Test point: FiO2 digital display
Expected: > 18%

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

O2 sensor calibration failure

O2 sensor fails to calibrate; red X displayed and unit alarms

Ranked causes

1. Internal oxygen sensor depleted or damaged (occasional)

First check

Attempt O2 calibration procedure

Test point: Screen display
Expected: green Checkmark buttons at 21% and 100%

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

Over pressure alarm patient safety

Intermittent high level audible alarm, warning bar flashes, O2 digital display flashes, digital O2 alarm low limit highlighted, alarm button flashes.

Ranked causes

1. Patient pressure exceeds 11 cmH2O in BiPhasic mode (unknown)

First check

Measure patient pressure

Test point: Pressure display
Expected: Below 11 cmH2O

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

Over pressure condition patient safety

Pressure exceeds safe limits; software opens dump valve to release pressure

Ranked causes

1. Excessive system pressure (occasional)

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

Over pressure in BiPhasic or BiPhasic Tr mode patient safety

Pressure display flashes, Warning Bar flashes, intermittent high level audible alarm, Alarm Button flashes, digital O2 alarm low limit highlighted.

Ranked causes

1. Patient pressure exceeds 11 cmH2O in BiPhasic or BiPhasic Tr mode (common)

First check

Monitor pressure display

Test point: Patient pressure reading
Expected: ≤ 11 cmH2O

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

Over pressure in nCPAP mode patient safety

Pressure display flashes, Warning Bar flashes, intermittent high level audible alarm, Alarm Button flashes, dump valve actuated for three seconds.

Ranked causes

1. Patient pressure exceeds 11 cmH2O in nCPAP mode (common)

First check

Monitor pressure display

Test point: Patient pressure reading
Expected: ≤ 11 cmH2O

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

Oxygen blender output not matching set value patient safety

Measured oxygen concentration differs from blender setting by more than 3%

Ranked causes

1. Oxygen sensor calibration drift (occasional)

First check

Set oxygen blender and allow stabilization

Test point: %O2 control and measured FiO2 display
Expected: Measured value within 3% of set value, ±3%

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

Oxygen cell calibration error patient safety

Difference between displayed and set oxygen value.

Ranked causes

1. Oxygen cell incorrectly calibrated, damaged or depleted (occasional)

First check

Compare displayed O2 with set value

Test point: Oxygen display
Expected: Match between displayed and set oxygen percentage

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

Power cord removal and installation high voltage

Procedure to safely disconnect and reconnect the power cord from the Infant Flow SiPAP unit

Ranked causes

1. Power cord requires replacement or maintenance (unknown)

First check

Power cord physically disconnected from AC mains

Test point: AC power source
Expected: No power connection

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

Screen displays in negative image during power-up

Screen shows inverted/negative image during power-up check sequence.

Ranked causes

1. Normal power-up check sequence (common)

First check

Screen image is negative

Test point: Display screen
Expected: Negative image display during power-up checks

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

Software fault

Intermittent high level audible alarm, Warning Bar flashes intermittently, screen displays flashing error code.

Ranked causes

1. Software failure detected (rare)

First check

Note error code displayed

Test point: Screen error code display
Expected: Specific error code per Chapter 9

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

Software fault alarm

Intermittent high level audible alarm, warning bar flashes intermittently, screen displays flashing fault code (E number).

Ranked causes

1. Software error detected during operation (rare)

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

Software not running with unit connected to power

Constant audible alarm, warning bar on, screen displays flashing fault code (E number).

Ranked causes

1. Software failed to start or load (rare)

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

Software not running with unit connected to power

Constant audible alarm, Warning Bar on, screen displays flashing error code.

Ranked causes

1. Software process failed to start on boot with power connected (rare)

First check

Note error code on screen

Test point: Screen error code display
Expected: Specific error code per Chapter 9

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

Error codes

Code	Meaning	Trigger	Severity
`-`	Battery too discharged to operate LCD and valve circuits	Battery voltage below 6.5 V with no external power	critical
`-`	Battery too discharged to operate LCD and valve circuits	Battery voltage drops below 6.5 V with no external power	critical
`-`	Program memory checksum error	Software corruption during execution	critical
`-`	Program memory checksum error	Software becomes corrupted during operation or storage	critical
`-`	Battery voltage too low for valve operation but LCD operable	Battery voltage between 6.5 V and 10 V with no external power	critical
`Discharged battery`	Battery voltage is too low to power the circuits	Battery charge drops below operating minimum	warning
`E10`	Non-volatile memory fault	Configuration or calibration data storage failure	error
`E10`	Non-volatile memory fault	Non-volatile memory failure	critical
`E11`	Calibration data lost	Loss of calibration data in memory	critical
`E11`	Calibration data lost	Sensor calibration data erased or unreadable from memory	error
`E12`	DIP settings mismatch or Patient Trigger board issue	DIP switch settings or PT PRESENT status differs from stored configuration	error
`E12`	Configuration DIP settings mismatch	DIP settings or PT PRESENT differ from non-volatile record	error
`E20`	Charged battery voltage too low	Battery voltage below 11 V under test load	warning
`E20`	Charged battery voltage too low	Battery voltage drops below 11 V under test load	warning
`E21`	External supply voltage too low to charge battery	AC supply voltage below 14 V when attempting to charge flat battery	error
`E21`	External supply voltage too low to charge battery	External supply voltage below 14 V	error
`E22`	Analog supply rails out of limits	Analog power supply voltage exceeds acceptable range	critical
`E22`	Analog supply rails out of limits	Power supply voltages for analog circuits exceed acceptable range	error
`E23`	Valve driver supply rails out of limits	Power supply voltages for valve driver circuits exceed acceptable range	error
`E23`	Valve driver supply rails out of limits	Valve driver power supply voltage exceeds acceptable range	critical
`E24`	Hardware safe-start watchdog disabled	Watchdog function failure preventing safe valve operation	critical
`E24`	Hardware safe-start watchdog disabled	Watchdog timer fails to enable valve control during startup	error
`E30`	Pressure sensor fault (ADC hits rail)	Pressure sensor analog-to-digital converter unable to convert signal	error
`E30`	Pressure sensor fault	Pressure sensor ADC hits rail indicating sensor failure	critical
`E31`	Zero valve not connected	Zero valve connection lost or not detected via sense line	critical
`E31`	Zero valve not connected (via sense)	Zero valve feedback signal not detected by pressure monitoring circuit	error
`E32`	Zero valve activation fault (via sense)	Zero valve feedback does not respond to activation command	error
`E32`	Zero valve activation fault	Zero valve fails to activate as detected via sense line	critical
`E33`	Unable to auto zero pressure sensor	Pressure sensor auto-zero function fails during startup	critical
`E33`	Unable to auto zero pressure sensor	Pressure sensor fails to reach zero calibration point	error
`E41`	Dump valve not connected (via sense)	Dump valve feedback signal not detected	warning
`E41`	Dump valve not connected	Dump valve connection lost or not detected via sense line	error
`E42`	Dump valve activation fault	Dump valve fails to activate as detected via sense line	error
`E42`	Dump valve activation fault (via sense)	Dump valve feedback does not respond to activation command	warning
`E50`	Oxygen sensor failure	Oxygen sensor malfunctions during normal operation	error
`E50`	Oxygen sensor fault	Oxygen sensor ADC hits rail indicating sensor failure	critical
`E51`	Oxygen sensor cannot be calibrated	User calibration fails with bad offset or high gain	critical
`E51`	Oxygen sensor failure variant	Oxygen sensor malfunction during operation	error
`E52`	Oxygen sensor failure variant	Oxygen sensor malfunction during operation	error
`E52`	Oxygen sensor calibrates but fuel cell worn out	O2 sensor calibration succeeds but shows low gain indicating fuel cell degradation	critical
`E53`	Oxygen sensor too noisy to calibrate	O2 sensor calibration timeout due to excessive noise	critical
`E53`	Oxygen sensor failure variant	Oxygen sensor malfunction during operation	error
`E54`	Oxygen calibration suspect (out of range)	O2 value measured outside normal range of 18-104%	error
`E54`	Oxygen sensor failure; high-elevation calibration issue	Oxygen sensor malfunction or high-altitude initialization (>6,600 feet or 2,000 meters)	error
`E54`	Oxygen calibration suspect	Oxygen reading measured outside valid range 18–104%	error
`E55`	Internal oxygen monitor disabled	User presses and holds alarm mute/reset button for 3 seconds, or oxygen sensor failure recovery	warning
`E61`	nCPAP Pressure high valve not connected	Pressure high valve feedback signal not detected	warning
`E61`	NCPAP Pres high valve not connected	NCPAP pressure high valve connection lost or not detected via sense	error
`E62`	NCPAP Pres high valve activation fault	NCPAP pressure high valve fails to activate as detected via sense	error
`E62`	nCPAP Pressure high valve activation fault	Pressure high valve feedback does not respond to activation	warning
`E70`	Patient Trigger module fault	PT module not responding or CAN bus communication failure	error
`E70`	PT module fault	Patient Trigger module failure (PTRDY or CAN bus failure)	warning
`E71`	No breath signal from PT module	No breath signal detected although CAN bus reports normal status	warning
`E71`	No breath signal from PT module	PT module not sending breath signal despite no apnea reported	error
`E72`	No trigger signal from PT module in BiPhasic Tr mode	PT module fails to send trigger signal in BiPhasic Trigger mode	error
`E72`	No trigger signal from PT module in BiPhasic Tr mode	PT module fails to provide trigger signal in BiPhasic Tr mode	warning
`E80`	Audible Alarm Module not functioning	Alarm output circuit fails to produce audible alert	warning
`E90`	Abnormal hardware, software or watchdog reset	Unplanned system reset detected during normal operation	warning
`E90`	Abnormal hardware, software or watchdog reset	Unexpected system reset during operation	critical
`E90*`	Spurious software interrupt or hardware failure	Software interrupt, crystal failure, stack overflow/underflow, or CPU exception	critical
`E91`	Internal software error detected	Software integrity check fails	critical
`E91`	Internal software error detected	Software error detection routine identifies fault in firmware execution	error
`E99`	Unknown error detected	Error condition detected but error code generator unable to classify	error
`E99`	Unknown error detected	Unidentified error condition triggered	critical
`E (number)`	Software fault, software not running, BiPhasic mode failure, or battery fault	Software error detected or fails to load, or BiPhasic mode cannot operate as set, or battery disconnected/failing	critical
`Fault Lockout`	Software-detectable fault that prevents unit from operating correctly	Internal fault detected during operation	error
`Loss of Power`	Complete loss of both AC power and battery power	AC power disconnected and battery depleted simultaneously	critical
`Oxygen cell calibration error`	Oxygen cell is incorrectly calibrated, damaged, or depleted causing disparity between displayed and set O2 value	Automatic monitoring detects oxygen cell error	warning

Likely causes and actions for each code are in ServiceForge. Connect ServiceForge to your AI

Community

0 fixes logged by technicians through their AI, with outcomes, for this model.

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