Patient monitors

Welch Allyn Patient Monitor 6200: troubleshooting and error codes

The ServiceForge knowledge base holds 49 documented symptoms for the Welch Allyn Patient Monitor 6200, with 130 ranked causes, 116 diagnostic checks with test points and expected values, and 1 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

Printer motor does not run

Printer motor fails to start or spin when paper advance is initiated; device does not respond to print commands

Ranked causes

1. Unit not configured for printer operation (common)
2. Printer PCB to motor cable disconnected or damaged (occasional)
3. Printer PCB to main board cable disconnected or damaged (occasional)
4. Motor gear misaligned with first plastic gear (occasional)
5. Paper jam blocking motor (common)
6. Printer PCB failure (occasional)
7. CPU board failure preventing printer operation (rare)

First check

Check system printer configuration setting

Test point: Configuration menu or display freeze duration
Expected: Unit configured for printer; no 10-second freeze on print

4 more checks with pass and fail actions, 7 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Blood pressure manometer accuracy out of specification patient safety

Measured pressure readings fail accuracy calibration test; readings consistently off from expected values; measurement drift or bias error

Ranked causes

1. Pump pressure capacity insufficient; needs verification and retest (common)
2. Check valve direction incorrect or malfunction (occasional)
3. Pneumatic leaks preventing stable pressure measurement (occasional)
4. Tubing kinked or blocked restricting accurate measurement (occasional)
5. Pressure transducer failure or measurement circuit fault (occasional)
6. Lifted pins on CPU connector JP8 (occasional)

First check

Verify pump pressure capacity ≥300 mmHg

Test point: BP pump output
Expected: Pressure reaches 300+ mmHg

3 more checks with pass and fail actions, 6 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Blood pressure overpressure limit out of specification patient safety

Overpressure protection fails; system exceeds safe pressure limits; safety interlock may not function properly

Ranked causes

1. Pump capacity insufficient; needs verification (common)
2. Check valve reversed or failed (occasional)
3. System leak preventing overpressure detection (occasional)
4. Tubing pinched or blocked (occasional)
5. Pressure transducer or comparator circuit failure on main board (occasional)
6. CPU board failure in overpressure logic (rare)

First check

Verify pump can exceed 300 mmHg

Test point: BP pump test circuit
Expected: Pressure reaches 300+ mmHg

3 more checks with pass and fail actions, 6 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

ETCO2 system failure, sensor unresponsive

ETCO2 system does not respond; pump does not activate; water trap switch failure or board malfunction

Ranked causes

1. Water trap receptacle switch broken or intermittent (common)
2. Service module board ID mismatch or configuration error (occasional)
3. Pump not responding to water trap switch activation (occasional)
4. Water trap receptacle switch intermittent; needs replacement (occasional)
5. Pryon board failure (occasional)
6. CPU board failure preventing ETCO2 operation (rare)

First check

Test water trap receptacle switch activation

Test point: Water trap switch and pump response
Expected: Pump activates when switch is pressed or water trap inserted

2 more checks with pass and fail actions, 6 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Unit does not power up, no AC or power LED caution

Device completely unresponsive; AC indicator LED dark; power-on LED not illuminating

Ranked causes

1. AC power cord disconnected or damaged (common)
2. Power supply not connected to main board (occasional)
3. Power supply 12V output failure (occasional)
4. Power supply defective (occasional)
5. Main board to display board cable disconnected or damaged (occasional)
6. Display board failure (occasional)

First check

Verify AC power present at outlet

Test point: Power outlet
Expected: AC power available

2 more checks with pass and fail actions, 6 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Blood pressure pump cannot exceed pressure limit, 'Can't pump beyond' error

System fails to reach target pressure; pump output limited; message displayed indicating maximum pressure not achieved

Ranked causes

1. Test incomplete or pump function normal; needs retest after verification (common)
2. Check valve installed in wrong direction or failed (occasional)
3. Pneumatic leak in system preventing pressure buildup (occasional)
4. Tubing pinched or blocked restricting flow (occasional)
5. Pump mechanical failure or worn pump (occasional)

First check

Verify pump can reach 300 mmHg

Test point: BP pump pressure test circuit
Expected: Pressure reaches at least 300 mmHg without load

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

CRT displays no image despite correct main to CRT connection high voltage

No visible output on CRT screen; main board to CRT connection verified; flex cable or high voltage connection may be compromised

Ranked causes

1. Flex cable from deflection board to tube disconnected or damaged (common)
2. High voltage anode connection disconnected or loose (common)
3. Deflection board failure (occasional)
4. CRT tube failure (occasional)
5. CPU board failure (rare)

First check

Verify flex-cable from deflection board to tube

Test point: Flex-cable connectors at both ends
Expected: Cable fully seated and undamaged

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

Earth resistance exceeds specification limit patient safety

Ground continuity measurement fails; resistance between ground reference and equipment chassis exceeds safe limits; electrical safety hazard

Ranked causes

1. Motor ground wire loose or disconnected from power supply can (common)
2. Ground tab fastening screws loose (common)
3. Power supply PCB mounting screws loose (occasional)
4. AC harness quick-connect terminals loose at power supply (occasional)
5. Power supply PCB failure with ground circuit defect (occasional)

First check

Measure earth resistance (ground continuity)

Test point: Chassis ground reference
Expected: Less than equipment specification limit (typically <0.1 Ohm)
Tools: Digital multimeter with continuity or ohms measurement

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

SpO2 system displays fault message, no signal detected patient safety

'SpO2 fault' message appears on CRT; system does not detect or respond to SpO2 probe; measurement unavailable

Ranked causes

1. SpO2 probe disconnected or not functioning in test (common)
2. SpO2 board to main board cable disconnected or damaged (occasional)
3. Main board failure affecting SpO2 circuit (occasional)
4. SpO2 board failure or defect (occasional)
5. CPU board failure preventing SpO2 processing (rare)

First check

Test SpO2 probe functionality with finger placement

Test point: SpO2 finger cuff and signal detection
Expected: Signal detected when probe connected to finger; normal waveform visible

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

Unit does not power up, AC and power LEDs on caution

Device receives power (AC and power-on LEDs lit) but does not fully initialize or respond

Ranked causes

1. CPU board not fully seated (common)
2. CPU board failure (occasional)
3. Conformal coating contamination in J4 header (occasional)
4. Main board failure (occasional)
5. Display board failure (rare)

First check

Verify CPU board fully seated in socket

Test point: CPU board connector
Expected: Board fully inserted with all pins making contact

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

Blood pressure leak test fails specification

BP system fails leak test; pneumatic leakage detected; system cannot maintain pressure during test cycle

Ranked causes

1. Intermittent leak in system that may pass individual test on retry (occasional)
2. Leaking seals on tubing connections in BP assembly (common)
3. Lifted pins on CPU connector JP8 causing air leak path (occasional)
4. Check valve failure or blockage (occasional)

First check

Run leak test on individual unit

Test point: BP system leak test circuit
Expected: No pressure loss within specification during test cycle

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

Printer motor runs but paper does not advance

Motor spins and makes noise but paper feed fails; thermal head chattering or grinding sounds; paper remains stationary during print cycle

Ranked causes

1. Missing dowel pin in paper roller (common)
2. Missing bearings or gears in paper feed mechanism (occasional)
3. Printer PCB failure affecting motor control (occasional)
4. CPU board failure affecting print control (rare)

First check

Inspect roller for missing dowel pin

Test point: Paper roller shaft
Expected: Dowel pin present and secure

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

Printer outputs garbled or unreadable characters

Printed text is jumbled, contains unrecognizable characters, wrong spacing, or is otherwise corrupted; thermal print quality issue or data transmission error

Ranked causes

1. CPU board not fully seated or loose connection (common)
2. CPU board failure (occasional)
3. Printer to main board cable damaged or loose (occasional)
4. Printer PCB failure (occasional)

First check

Verify CPU board fully seated in socket

Test point: CPU board connector
Expected: All pins fully inserted and making contact

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

Printer produces light or no print output

Printed output is faint, very light in color, or completely absent; thermal head may not be heating properly; paper may not be making proper contact

Ranked causes

1. Paper installed incorrectly with thermal side not visible (common)
2. Printer PCB to print head cable disconnected or damaged (occasional)
3. Printer thermistor circuit failure or strobe width setting too low (occasional)
4. Print head force or pressure too light on paper (occasional)

First check

Verify paper installed correctly with thermal side visible

Test point: Paper orientation in printer
Expected: Thermal (shiny) side facing print head and visible

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

Unit powers up but no image on CRT display caution

Device starts and LEDs power on but CRT screen remains blank or black; no image output to monitor

Ranked causes

1. Conformal coating in J4 header (occasional)
2. CPU board defective (occasional)
3. Main to deflection board connection incorrect or damaged (occasional)
4. CPU assembly failure (occasional)

First check

Inspect J4 header for conformal coating

Test point: J4 connector on board
Expected: No coating contamination visible

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

Display segments stay on at power-up

Most or all of display segments remain illuminated when unit powers on; display does not clear to show normal startup state

Ranked causes

1. CPU board failure (common)
2. Display board to main board cable failure (occasional)
3. Power supply failure affecting display circuit (occasional)

First check

Verify display board to main board cable connection

Test point: Cable connectors at both ends
Expected: Connectors fully seated

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

NIBP overpressure detected patient safety

Audible alarm and 'Check blood pressure cuff' message displayed; NIBP pump and valve drive signals opened

Ranked causes

1. Cuff pressure >=10 mmHg for 295 seconds (common)
2. Cuff pressure >=15 mmHg for 175 seconds (common)
3. Cuff pressure >295 mmHg for 0.5 seconds (occasional)

First check

Monitor digitized primary transducer output for sustained overpressure condition

Test point: PrimaryPres A/D input
Expected: <10 mmHg (nominal)

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

Power on self-test fails or displays incorrect response

Monitor does not display expected LEDs, beeps, dashes, or CRT screen content after power on; indicates hardware or firmware issue.

Ranked causes

1. Power button LED or audio alarm circuit failure (common)
2. CRT display failure to illuminate or show content (common)
3. Measurement parameters not displaying expected dash patterns or values (occasional)

First check

Plug monitor into AC power outlet and verify AC~ LED indicator is lit

Test point: AC power input connector; AC~ LED on front panel
Expected: AC~ LED is illuminated (no flickering); stable power detected
Tools: AC power outlet with ground; multimeter for voltage check if needed

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

Temperature measurement system failure or disconnection

Temperature probe disconnected, unresponsive, or measurement circuit failure; no temperature reading displayed

Ranked causes

1. Temperature probe to main board connection loose or disconnected (common)
2. Temperature probe connector pins not properly seated (occasional)
3. Main board temperature measurement circuit failure (occasional)

First check

Verify temperature probe cable connected to main board jack

Test point: Main board temperature connector
Expected: Cable fully and securely connected

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

Blood pressure deflation profile out of specification

Cuff deflation rate or curve does not match expected specification; deflation too fast or irregular; system dump valve malfunction

Ranked causes

1. Dump valve failure or malfunction (common)
2. Main board valve drive circuitry fault (occasional)

First check

Verify deflation profile rate and regularity

Test point: System deflation during measurement cycle
Expected: Smooth, continuous deflation at specified rate (exact rate per specification document)

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

Blood pressure dwell pressure out of specification

Pressure level at dwell point does not match specified value; typically 15 mmHg detection point accuracy or consistency issue

Ranked causes

1. Main board 15 mmHg detection circuit fault (occasional)
2. CPU board firmware or logic error affecting dwell detection (occasional)

First check

Measure dwell pressure value

Test point: System dwell detection at specified point
Expected: Dwell pressure equals specification value, typically 15 mmHg (see specification doc)

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

Blood pressure dwell time out of specification

Time interval between start of measurement and 15 mmHg detection point incorrect; dwell timing does not meet specification

Ranked causes

1. Main board 15 mmHg detection circuit fault (occasional)
2. CPU board timer circuit fault (occasional)

First check

Measure dwell time interval

Test point: System dwell measurement
Expected: Dwell time within specification (consult specification document for exact limits)

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

BP SYSTEM FAULT displayed patient safety

'BP SYSTEM FAULT' message on CRT display; NIBP system disabled; redundant safety transistor opens to ensure pump off and valve open

Ranked causes

1. Primary transducer pressure >330 mmHg (nominal trip 314 mmHg) (rare)
2. Primary transducer pressure >15 mmHg (nominal 13.3 mmHg) for three minutes (rare)

First check

Monitor primary transducer output voltage for hardware overpressure fault conditions

Test point: U203A/B comparator inputs, PrimaryPres signal
Expected: 0.75 V at 0 mmHg; 4.0 V at 300 mmHg (with 5 V supply)

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

CRT displays only horizontal center line

CRT shows only a horizontal line across center of screen; no vertical scan or full raster; vertical deflection absent

Ranked causes

1. Yoke to CRT board cable problem (common)
2. Deflection board failure (occasional)

First check

Verify yoke cable connected to CRT board

Test point: Yoke cable connectors
Expected: Cable fully seated at CRT board end

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

CRT shows glow only at bottom of screen

Dark glow visible at bottom edge of CRT display; minimal or no image in upper and middle portions of screen

Ranked causes

1. Conformal coating in J4 header on circuit board (occasional)
2. CPU board failure affecting display circuitry (occasional)

First check

Inspect J4 header on CPU or main board

Test point: J4 connector
Expected: No conformal coating residue visible

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

ETCO2 system fails specification for flow rate or percentage

Capnography measurements fail accuracy or flow rate specification limits; readings outside acceptable range

Ranked causes

1. System requires calibration or calibration needs repeating (common)
2. Pryon board failure affecting measurement accuracy (occasional)

First check

Perform ETCO2 calibration procedure

Test point: Calibration sequence and results
Expected: Specification limits met after calibration

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

Monitor does not power on or immediately powers off caution

No response to power button; monitor shuts down shortly after turning on; AC LED not lit or unstable.

Ranked causes

1. AC power not present or unstable (common)
2. Battery depleted (models 622/623 only) (occasional)

First check

Verify AC power outlet is functional using a known-good device (lamp, charger, etc.)

Test point: AC power outlet receptacle
Expected: Test device powers on normally; outlet is live with stable voltage
Tools: Lamp or another AC device to test outlet

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

NIBP Fault Message displayed patient safety

NIBP system disabled; transducer outputs disagree or A/D reference voltage measurement error detected

Ranked causes

1. Primary and safety transducer outputs disagree (occasional)
2. A/D reference voltage measurement error (occasional)

First check

Compare digitized primary and safety transducer outputs

Test point: SafetyPres and PrimaryPres A/D inputs
Expected: Within calibrated range; typically <5% disagreement

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

Print on Alarm function not working

Printer does not print automatically when alarm condition triggers, or prints when it should not

Ranked causes

1. Print on Alarm setting disabled (common)
2. Alarm condition not triggering (occasional)

First check

Access Advanced Configuration menu and disable Print on Alarm

Test point: Print on Alarm setting in Configuration menu
Expected: Print on alarm set to No

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

SpO2 signal accuracy out of specification patient safety

Measured SpO2 values do not match expected accuracy; readings drift or are inconsistent with reference values

Ranked causes

1. Nellcor probe ribbon cable or harness damaged (occasional)
2. SpO2 board failure or sensor circuit defect (occasional)

First check

Visually inspect probe ribbon cable for damage

Test point: Probe connector cable from SpO2 board
Expected: No visible kinks, tears, or pinching

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

Unit powers on intermittently or power button sticks caution

Device intermittently powers on and off; power button physically sticks or power-on operation cannot be consistently reproduced; unit passes burn-in testing

Ranked causes

1. Flashing on bezel interfering with power button (occasional)
2. Power button LED tipped or misaligned on display board (occasional)

First check

Inspect bezel flashing around power button

Test point: Bezel surface near power button
Expected: No flashing material present

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

Blood pressure alarm cannot be silenced patient safety

Audio alarm continues after pressing BP ALARMS OFF button; visual alarms remain active; red LED in button not illuminating

Ranked causes

1. BP ALARMS OFF button or alarm mute circuit failure (unknown)

First check

Verify audio alarm silences

Test point: Atlas speaker
Expected: Audio alarm silent

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

Blood pressure alarm not triggering on overpressure patient safety

No audio alarm, no visual 'Check Blood Pressure Cuff' message, no flashing SYSTOLIC/DIASTOLIC LEDs when finger blocks BP port

Ranked causes

1. Alarm system malfunction (unknown)

First check

Verify audio alarm sounds

Test point: Atlas speaker
Expected: Audio alarm audible

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

Blood pressure alarm triggers at timeout without cuff connection patient safety

Audio and visual alarms trigger at 60 seconds with no cuff attached; SYSTOLIC and DIASTOLIC LEDs flash

Ranked causes

1. Normal cuff disconnection detection behavior (common)

First check

Verify alarm triggers at 60 seconds

Test point: System timer and alarm circuit
Expected: Audio and visual alarm at 60 second mark

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

Blood pressure diastolic high alarm does not trigger patient safety

No audio alarm or LED flash when diastolic pressure exceeds high alarm threshold of 70 mmHg

Ranked causes

1. Diastolic HI alarm threshold not set or alarm circuit failure (unknown)

First check

Verify DIASTOLIC HI alarm threshold set

Test point: SELECT and SET buttons, DIASTOLIC LED display
Expected: 70 mmHg displayed after setting

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

Blood pressure diastolic low alarm does not trigger patient safety

No audio alarm or LED flash when diastolic pressure drops below low alarm threshold of 90 mmHg

Ranked causes

1. Diastolic LO alarm threshold not set or alarm circuit failure (unknown)

First check

Verify DIASTOLIC LO alarm threshold set

Test point: SELECT and SET buttons, DIASTOLIC LED display
Expected: 90 mmHg displayed after setting

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

Blood pressure systolic high alarm does not trigger patient safety

No audio alarm or LED flash when systolic pressure exceeds high alarm threshold of 130 mmHg with simulator set to 140/80

Ranked causes

1. Systolic HI alarm threshold not set or alarm circuit malfunction (unknown)

First check

Verify SYSTOLIC HI alarm threshold is set correctly

Test point: SELECT and SET buttons, SYSTOLIC LED display
Expected: 130 mmHg in LED display after setting

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

Blood pressure systolic low alarm does not trigger patient safety

No audio alarm or LED flash when systolic pressure drops below low alarm threshold of 160 mmHg with simulator at 140/80

Ranked causes

1. Systolic LO alarm threshold not set or alarm circuit malfunction (unknown)

First check

Verify SYSTOLIC LO alarm is set correctly

Test point: SELECT and SET buttons, SYSTOLIC LED display
Expected: 160 mmHg displayed after setting

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

Calibration Failed message

Calibration fails during ET CO2 calibration procedure

Ranked causes

1. System date set to 2022 or later (common)

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

Calibration: Blood pressure patient safety

BP calibration procedure using external pressure reference and manometer connected to BP port via T-connectors

Ranked causes

1. Blood pressure calibration required (unknown)

First check

Verify HyperTerminal connection to COM1

Test point: PC COM1 port
Expected: Pangea> prompt displayed in HyperTerminal after pressing Enter

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

Calibration: BP (Blood Pressure)

BP calibration procedure using external pressure source and manometer to verify monitor accuracy

Ranked causes

1. Routine calibration setup (common)

First check

Verify date and time are correct on Atlas monitor

Test point: CLOCK button display
Expected: Current date and time match system time

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

Calibration: Safety transducer two-point

Factory or field recalibration of safety transducer gain and zero using two known pressure points and NVRAM storage

Ranked causes

1. Safety transducer loose initial accuracy (+/-50%) requires calibration (common)

First check

Measure safety transducer output at zero pressure

Test point: SafetyPres signal at P202-Out+/Out- (differential), or TP226
Expected: 0 mmHg reference; nominal gain 0.25 mV/mmHg with +/-25 mV zero offset

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

Capnography waveform not displayed

After capnography sensor warmup, pump motor sounds and initial waveform with respiration dashes shown, but waveform not updating with breathing

Ranked causes

1. Capnography sensor not detecting breath gas flow (common)

First check

Observe waveform response to gentle breathing

Test point: Display lower trace
Expected: Waveform visible within seconds of breathing

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

CRT displays dark vertical scan lines in image

Multiple dark vertical lines visible across CRT image, appearing as scan line artifacts or loss of horizontal resolution segments

Ranked causes

1. CPU board failure affecting display control (common)

First check

Verify CPU board operation

Test point: System startup and display processing
Expected: No scan line artifacts; clear image without vertical lines

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

CRT displays only center dot

CRT screen shows single dot in center of display with no horizontal or vertical scan; no image raster visible

Ranked causes

1. Yoke to CRT board cable disconnected or damaged (common)

First check

Verify yoke to CRT board cable connected

Test point: Cable connectors at both ends
Expected: Cable fully seated at yoke and CRT board

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

CRT image rotated or poorly aligned

Image displayed on CRT is tilted, skewed, or not properly centered on screen; alignment is off from expected position

Ranked causes

1. Yoke position incorrect or magnetic deflection misaligned (common)

First check

Inspect yoke positioning

Test point: CRT yoke mounting
Expected: Yoke aligned to display centered and upright image

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

CRT segment or LED out, buttons non-responsive

One or more display segments do not illuminate; individual LED indicators dark; front panel buttons unresponsive to input

Ranked causes

1. Display board failure (common)

First check

Verify display board power and connections

Test point: Display board connector
Expected: All connections secure and power present

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

Pangea Communication Protocol

Serial interface protocol for Atlas monitor interaction with computer; case-sensitive English commands with prompts

Ranked causes

1. Enable serial communication for calibration (common)

First check

Monitor for Pangea prompt after Atlas power-up

Test point: HyperTerminal display
Expected: Pangea> prompt appears
Tools: HyperTerminal on PC

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

Printer output darkness or legibility issues

Waveform printout too dark, too light, lines too thick/thin, text illegible, blurring or blooming of text

Ranked causes

1. Printer calibration not optimized (common)

First check

Connect ECG simulator and generate sample waveform

Test point: ECG simulator output to Atlas ECG input
Expected: Waveform appears on printout

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

Error codes

Code	Meaning	Trigger	Severity
`ECG Lead fault`	ECG cable disconnected or not properly connected	ECG cable is disconnected from the patient monitor	error

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.