Anesthesia machines · Fabius family

Dräger Fabius GS: troubleshooting and error codes

The ServiceForge knowledge base holds 26 documented symptoms for the Dräger Fabius GS, with 76 ranked causes, 130 diagnostic checks with test points and expected values, and 108 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

Fresh gas display blank or not working properly patient safety

Fresh gas flow meter display is blank, not responding, or showing incorrect readings

Ranked causes

1. Display configuration setting incorrect (2-gas vs 3-gas mismatch) (common)
2. Fresh gas flow sensors need recalibration (common)
3. Cable connections at flow sensors loose or damaged (occasional)
4. Cable from flow sensors to J16 on controller PCB damaged or disconnected (occasional)
5. Individual fresh gas flow sensor defective (occasional)
6. Cable from display PCB to controller PCB disconnected or faulty (occasional)
7. Fresh gas display PCB assembly defective (occasional)
8. Controller PCB assembly faulty (rare)

First check

Verify fresh gas displays are not working properly

Test point: Display output and reading accuracy
Expected: Blank, unresponsive, or incorrect readings

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

Ventilator inoperative patient safety

Ventilator assembly not functioning or delivering gas to breathing system

Ranked causes

1. Gasket, ventilator cover, hose connections or breathing system not secure (common)
2. Breathing bag or internal tubing damaged or improperly installed (common)
3. Roller diaphragm defective or vacuum system leak (occasional)
4. Pneumatic connections, vacuum supply, or cable connections faulty (occasional)
5. Ventilator diaphragms or motor defective (occasional)
6. Controller PCB assembly faulty (rare)

First check

Verify ventilator is not functioning properly

Test point: Ventilator output and bag operation
Expected: No ventilation or gas delivery

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

Incorrect or out-of-range voltage at controller PCB high voltage

Voltages measured at PCB connectors do not fall within acceptable ranges specified in Table 3-1

Ranked causes

1. External mains fuse open or faulty (common)
2. Battery fuse F4 open or faulty (common)
3. Battery fuse F1 open or faulty (common)
4. Distribution fuse F2 open or faulty (common)
5. Distribution fuse F3 open or faulty (common)

First check

Measure +28 VDC at power supply input connector

Test point: J6-1 (+28 VDC), J6-4 (Common)
Expected: 26.6 VDC to 29.4 VDC, 26.6 to 29.4 VDC
Tools: DMM

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

Loss of O2 monitor patient safety

Oxygen concentration display not functioning or reading

Ranked causes

1. Sensor cord not connected to interface panel (common)
2. Sensor element not installed correctly or expired (common)
3. Sensor housing defective (occasional)
4. Internal cable from interface to controller PCB open or disconnected (occasional)
5. Controller PCB assembly faulty (rare)

First check

Verify O2 sensor cord is connected to interface panel

Test point: Interface panel connector
Expected: Cord seated and connected

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

Loss of respiratory volume monitor patient safety

Respiratory volume measurement display not functioning or reading

Ranked causes

1. Sensor cord not connected to flow sensor (common)
2. Spirolog volume sensor not installed properly or connections not secure (common)
3. Spirolog volume sensor defective or worn (occasional)
4. Internal cable from interface to controller PCB open or disconnected (occasional)
5. Controller PCB assembly faulty (rare)

First check

Verify respiratory volume monitor is functioning

Test point: Monitor display output
Expected: Respiratory volume reading displayed normally

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

Main display blank upon system power-up patient safety

Display screen shows no output or activity when system is powered on

Ranked causes

1. Software download procedure performed immediately prior to failure (common)
2. Power supply voltage out of tolerance (occasional)
3. Display panel cable disconnected or faulty (occasional)
4. Display panel defective (occasional)
5. Controller PCB assembly faulty (rare)

First check

Verify display is blank upon system power-up

Test point: Main display screen
Expected: No display activity or output

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

Keypad inoperative patient safety

Keyboard or keypad buttons not responding to user input

Ranked causes

1. Keypad buttons have no tactile feedback or stuck (common)
2. Cable disconnected between keypad interface and controller PCB (occasional)
3. Monitor bezel assembly defective (occasional)
4. Controller PCB assembly faulty (rare)

First check

Verify keypad is not responding to input

Test point: Keypad buttons and system response
Expected: No response to key presses

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

Loss of breathing pressure monitor patient safety

Breathing pressure measurement display not functioning

Ranked causes

1. Pilot line and breathing gauge connections not secure (common)
2. Pressure monitor calibration out of specification (occasional)
3. Internal tubing from interface to controller PCB damaged or disconnected (occasional)
4. Controller PCB assembly faulty (rare)

First check

Verify breathing pressure monitor is functioning properly

Test point: Monitor display output
Expected: Pressure reading displayed normally

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

PMC certification level determination patient safety

Assessment and certification of Fabius GS machine based on equipment condition, NAD recommendations, and failure codes. Certification levels are A (Certified), B (Certified with Recommendations), C (Conditionally Certified), or D (No Certification), with additional modifiers I or II for operational constraints.

Ranked causes

1. Certification level A: No recommendations (unknown)
2. Certification level B: Certified with Recommendations (unknown)
3. Certification level C: Conditionally Certified (unknown)
4. Certification level D: No Certification (unknown)

First check

Identify applicable NAD recommendations and codes for machine

Test point: NAD Recommendation Guidelines Index Anesthesia Systems Part Number S010250
Expected: All applicable recommendations and their certification codes (A, B, C, D, I, II) identified

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

Serial port communication failure

Host unit cannot communicate with peripheral device through serial port

Ranked causes

1. Peripheral cable not connected to communication port (common)
2. Serial port configuration mismatch (common)
3. Internal communication port cable open or disconnected (occasional)
4. Controller PCB assembly faulty (rare)

First check

Verify host and peripheral communication status

Test point: Serial communication link status indicator
Expected: Host communicates successfully with peripheral device

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

No audio alarms patient safety

Audible alarm function not working; no alarm sounds are produced

Ranked causes

1. Cable disconnected between front panel keypad and controller PCB (common)
2. Front panel monitor bezel defective (occasional)
3. Controller PCB assembly faulty (rare)

First check

Verify audio alarm function is not working

Test point: Speaker/alarm output
Expected: No audio output during alarm condition

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

No oxygen supply pressure alarms patient safety

Low oxygen supply pressure alarm not triggering when oxygen pressure is insufficient

Ranked causes

1. Low O2 supply pressure switch, wire harness, or display PCB connections faulty (common)
2. Fresh gas display PCB defective (occasional)
3. Controller PCB assembly faulty (rare)

First check

Verify no O2 in system and check alarm function

Test point: Oxygen supply pressure sensor and alarm output
Expected: Low O2 supply pressure alarm triggered with no O2 pressure

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

PEEP valve calibration fails caution

PEEP calibration process displays Fail message on completion instead of Pass

Ranked causes

1. Invalid or incomplete pressure calibration (common)
2. Test hose improper connection (occasional)
3. System leak during calibration (occasional)

First check

Verify pressure calibration status

Test point: Service menu calibration history
Expected: Valid pressure calibration present, no 'Inv pres. cal' message

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

PMS parts replacement schedule

Scheduled replacement of consumable and wear parts for Fabius GS during periodic manufacturer service. Includes flow sensors, O2 sensors, O-rings, valve discs, filters, diaphragms, batteries, and sealed assemblies.

Ranked causes

1. Annual maintenance parts replacement required (common)
2. 3-year maintenance parts replacement required (common)
3. Proper disposal of batteries and O2 sensors required (common)

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

Fresh Gas Flow Calibration result Fail

Calibration procedure resulted in Fail status at Store Zero step

Ranked causes

1. Residual gas flow when valves closed (common)
2. Sensor malfunction or drift (occasional)

First check

Inspect all flow control valves for proper closure

Test point: Flow control valves
Expected: All valves fully seated

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

Unit does not power on high voltage

Machine fails to start when power is applied; no lights or display indication

Ranked causes

1. External mains fuse blown (common)
2. Battery fuse F4 open circuit (common)

First check

Verify mains power at unit input

Test point: Power entry connector
Expected: Mains voltage present
Tools: DMM or power indicator

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

'Inv pres. cal' message appears during PEEP calibration setup caution

Invalid pressure calibration message displayed when attempting PEEP valve calibration

Ranked causes

1. Pressure calibration not completed (common)

First check

Access calibration menu and select pressure calibration

Test point: Service menu Calibration option
Expected: Pressure calibration option available

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

Battery pack internal fault or disconnection caution

Series-connected 12 V battery cells not functioning or disconnected internally

Ranked causes

1. One or both 12 V battery cells failed or disconnected (rare)

First check

Verify battery cell series connection integrity

Test point: J5 connector on main controller PCB assembly
Expected: Two series 12 V cells = ~24 V nominal minimum, 27–29.6 V at full charge
Tools: Voltmeter/DMM

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

Battery voltage out of specification caution

Backup battery voltage measurement not within acceptable range during AC operation or battery operation

Ranked causes

1. Battery cells degraded or charge insufficient (common)

First check

Measure total battery voltage during AC operation at full charge

Test point: J5 connector on main controller PCB assembly
Expected: 27.0 to 29.6 V, ±2.6 V
Tools: Voltmeter/DMM

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

Calibration: Cylinder Pressure Regulator caution

Adjust oxygen, nitrous oxide, or air cylinder pressure regulator output to specified pressure range

Ranked causes

1. Regulator output pressure requires calibration (common)

First check

Set System Power switch to OFF

Test point: System Power switch
Expected: OFF

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

Calibration: Fabius GS periodic manufacturer service patient safety

Complete periodic manufacturer's service (PMS) calibration and certification procedure for Fabius GS anesthesia machine. Includes electrical safety, system diagnostics, battery circuit, configuration, service data, calibrations, site configurations, scavenger, breathing system, vapor interlock, yokes and gauges, gas inlet regulator, cylinder regulator, high pressure leak, oxygen supply failure protection, flowmeters, oxygen monitor, oxygen concentrations, SORC, pressure monitor, ventilator, volume alarms, audio silence, oxygen flush valve, and final tests.

Ranked causes

1. PMS calibration and certification required (common)

First check

Verify calibration of all test equipment

Test point: Calibration labels on multimeter, electrical safety analyzer, pressure gauge, flowmeter test stand, digital pressure man
Expected: All labels show current calibration dates

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

Calibration: PEEP

PEEP valve calibration procedure. A valid pressure calibration must be completed first. Verify PEEP calibration passes.

Ranked causes

1. Valid pressure calibration not performed (common)

First check

Verify valid pressure calibration is stored

Test point: System memory/calibration history
Expected: Valid pressure calibration present (no 'Inv pres. cal' message)

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

Configuration: Model Type (Software Version 2.X)

Verify Model Type listed on system screen is consistent with actual unit. Do not change unless required by software download or PCB replacement.

Ranked causes

1. Model Type changed incorrectly (rare)

First check

Verify software version is 2.X or later

Test point: System Settings screen
Expected: Software Version 2.X displayed (if applicable)

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

O2 Supply Alarm Activates Outside Acceptable Range patient safety

Oxygen supply alarm triggers at pressure below 16 psi or above 24 psi instead of within the correct range

Ranked causes

1. Alarm set screw adjustment out of specification (common)

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

Power supply replacement high voltage

Procedure to replace the power supply unit mounted on the controller assembly back panel

Ranked causes

1. Power supply failure or malfunction requiring replacement (unknown)

First check

Set main power switch to OFF

Test point: Main power switch
Expected: OFF position

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

Vapor interlock system malfunction patient safety

Multiple vaporizers can be adjusted simultaneously instead of being locked to prevent concurrent use

Ranked causes

1. Vapor interlock mechanism failure (unknown)

First check

Left vapor interlock function

Test point: Left vaporizer handwheel
Expected: Right vaporizer handwheel cannot be adjusted when left is set above zero

2 more checks 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
`APNEA FLOW !!!`	No airflow detected; high-level apnea alarm	No airflow detected for 26-34 seconds after breathing circuit disconnection	critical
`APNEA FLOW !!`	No airflow detected; mid-level apnea alarm	No airflow detected for 13-17 seconds after breathing circuit disconnection	error
`APNEA PRESSURE !!!`	No airway pressure detected; high-level apnea alarm	No airway pressure detected after breathing circuit disconnection	critical
`C001`	Handler Busy	Communication error during device handler operation	warning
`C002`	Incoming Overflow	Incoming communication buffer overflow	warning
`C003`	Outgoing queue overflow	Outgoing communication queue overflowed	warning
`C004`	Message not registered	Communication message failed to register	warning
`C005`	Character not transmitted	Character transmission failed	warning
`C006`	Interrupt problem	Hardware interrupt handling failure	error
`C007`	Continuous interrupts	Continuous interrupt generation	error
`C008`	Excessive Breaks	Excessive break signals on communication line	warning
`C009`	Excessive Framing	Excessive framing errors in communication	warning
`C010`	Excessive Parity	Excessive parity errors detected	warning
`C011`	Excessive Overrun	Excessive overrun errors in communication	warning
`C012`	Non-existent UART	UART port not detected	critical
`CONDITIONALLY FUNCTIONAL`	Minor problem has been detected during diagnostics	Power-up self-test completion with minor issue	warning
`F001`	Diag Watchdog	Watchdog timer expired during diagnostics	critical
`F002`	Diag System Ram	System RAM fails on power up	critical
`F003`	Diag Program Memory	Flash memory error detected on startup	critical
`F004`	Diag Video Test	Video memory or display failed	error
`F005`	Diag Interrupts	Interrupt handling test failed	error
`F006`	Diag A/D Converter	Analog-to-digital converter test failed	error
`F007`	Diag NM Ram	Non-volatile memory corruption detected on startup	error
`F008`	Diag Serial Port	Serial port loopback test failed on startup	error
`F009`	Diag Clock	System clock test failed	critical
`F010`	Diag Speaker	Speaker not detected on power up	warning
`F011`	Diag Main Power	Mains power not detected on power up	error
`F012`	Diag Battery	Battery voltage below 20% on power up	warning
`FG01`	N2O CAL ERR	N2O sensor value out of range during calibration	error
`FG02`	AIR CAL ERR	AIR sensor value out of range during calibration	error
`FG03`	O2 CAL ERR	O2 sensor value out of range during calibration	error
`FLOW SENSOR FAIL !`	Respiratory volume sensor or flow sensor malfunction	Respiratory volume sensor cord disconnected from flow sensor	error
`FRESH GAS LOW !!`	Fresh gas flow insufficient	Fresh gas flow below minimum threshold for 30 seconds or when inspiratory port disconnected	warning
`FUNCTIONAL`	Fabius GS has passed all power-up tests and is fully functional	Power-up self-test completion	info
`I001`	CPU Diag Recovery	CPU recovered from bad initialization	warning
`I011`	L2 SW Watchdog	Level 2 software watchdog timer expired	critical
`I012`	L2 Recovered, wLevelTwoErrorCount	Level 2 software watchdog timeout with recovery	warning
`I021`	L3 SW Watchdog	Level 3 software watchdog timer expired	critical
`I022`	L3 Recovered, wLevelThreeErrorCount	Level 3 software watchdog timeout with recovery	warning
`I031`	L4 SW Watchdog	Level 4 software watchdog timer expired	critical
`I032`	L4 Recovered, wLevelFourErrorCount	Level 4 software watchdog timeout with recovery	warning
`Inv pres. cal`	Invalid pressure calibration detected	Attempt to perform PEEP valve calibration without valid prior pressure calibration	error
`M001`	O2 <10%	Oxygen concentration drops below 10%	critical
`M002`	O2 LOW INOP	O2 sensor inoperative or disconnected	critical
`M003`	O2 DIFF HIGH	Oxygen difference between sensors exceeds threshold	error
`M004`	BATTERY <10%	Battery capacity drops below 10% during battery operation	critical
`M005`	BATTERY <20%	Battery capacity drops below 20% during battery operation	warning
`MINUTE VOLUME HIGH !!`	Minute volume exceeds high alarm threshold	Minute volume exceeds high alarm limit during ventilation	warning
`MINUTE VOLUME LOW !!`	Minute volume below low alarm threshold	Minute volume falls below low alarm limit during ventilation	warning
`No Fresh Gas !!!`	No fresh gas flow detected (software version 1.3n only)	No fresh gas flow detected when No Fresh Gas mode is enabled (version 1.3n)	critical
`NON-FUNCTIONAL`	Serious problem has been detected; machine will not proceed to Monitor screen	Power-up self-test completion with critical failure	critical
`NVC0`	Non-Matching CRCS	NVRAM CRCs for primary and secondary do not match	error
`NVF0`	Pri and Sec NV Files Inv	Both primary and secondary NVRAM files invalid	critical
`NVF1`	Pri NV File Inv	Primary NVRAM file invalid	error
`NVF2`	Sec NV File Inv	Secondary NVRAM file invalid	error
`NVP1`	Pat Check Pri Fail	NVRAM primary pattern write test failed	error
`NVP2`	Pat Check Sec Fail	NVRAM secondary pattern write test failed	error
`O2 Sensor Calibration Failed`	Oxygen sensor calibration procedure did not complete successfully	occurs during 21% O2 calibration step	error
`PS01`	Charger Error	Battery charger timeout or failure	warning
`PS02`	-2.5V Supply Failure	Negative 2.5V supply voltage out of range	error
`PS03`	+12V Supply Failure	Positive 12V supply voltage out of range	error
`PS04`	-5V Supply Failure	Negative 5V supply voltage out of range	error
`PS05`	Battery Less Than 18V	Battery voltage drops below 18V	warning
`PS06`	+28V Supply Failure	Positive 28V supply voltage out of range	error
`PS07`	Temp Sensor Failure	Temperature sensor voltage out of range	error
`PS08`	2.5V Supply Failure	Positive 2.5V supply voltage out of range	error
`PS09`	3.3V Supply Failure	Positive 3.3V supply voltage out of range	error
`PS10`	+10V Supply Failure	Positive 10V supply voltage out of range	error
`PS11`	+16V Supply Failure	Positive 16V supply voltage out of range	error
`S006`	Service Log Clear	Service log cleared by technician or software upgrade	info
`SS90`	test message	Factory test during manufacturing	info
`U001`	New Device ID Created	Device ID created due to NVRAM corruption or missing ID	warning
`U002`	Option Enabled	Secure option was enabled	info
`U003`	Option Disabled	Secure option was disabled	info
`U007`	Model Changed to FGS	Model type changed to FGS configuration	info
`U008`	Model Changed to Tiro	Model type changed to Tiro configuration	info
`U009`	Monitoring Disabled	Monitoring mode was disabled	warning
`U010`	Monitoring Enabled	Monitoring mode was enabled	info
`U012`	SOS Recovered	Secure Option Setting recovered after partial NVRAM corruption	warning
`U013`	FGS SOS Invalid	FGS Secure Options Setting NVRAM file corrupt, no recovery	error
`U014`	Tiro SOS Invalid	Tiro Secure Options Setting NVRAM file corrupt, no recovery	error
`V001`	VENT PEEP NOT CAL	Auto ventilation attempted without valid PEEP calibration	error
`V002`	ZERO POS INVALID	Light barrier crossing at bottom vent not detected	error
`V037`	EX VALVE LEAK	Excessive leak detected in exhalation valve	warning
`V042`	Motor Voltage Error	Motor voltage drops below minimum during auto ventilation	error
`V043`	MOTOR LIM STOP	Excessive motor current during auto ventilation	error
`V044`	MEMBRANE PRES LOW	Membrane vacuum below normal operating range	warning
`V045`	MEMBRANE PRES HIGH	Membrane vacuum above normal operating range	warning
`V049`	MOTOR OVER CURRENT	Persistent excessive motor current causing shutdown	critical
`V050`	LT Pres Failed>350	Leak test pressure exceeded 350 mbar	error
`V051`	LT Pres Rose>250	Leak test pressure rose more than 250 mbar	error
`V052`	LT SYS FAIL	Leak test system failure	error
`V053`	LT PC FAIL	Leak test pressure control failure	error
`V060`	Comp Unexp State	Compliance test entered unexpected state	error
`V061`	Comp Bag Pres Too High	Compliance test start pressure exceeds limit	error
`V062`	Comp Cant Fully Pres	Compliance test unable to achieve full pressurization	error
`V063`	Comp Cant Hold Pres	Compliance test unable to maintain plateau pressure	error
`V064`	COMPCant DePres	Pressure not decreasing during compliance test	error
`V065`	COMPInv Pres	Pressure changing in wrong direction during compliance test	error
`V066`	COMPInv Pres	Pressure changing in wrong direction during compliance test	error
`V067`	COMPSys < VentHose	Irregular compliance test results	warning
`V069`	Comp Unexpected Error	Compliance test entered unexpected error state	error
`V070`	COMPSys Fail in Range	Compliance value unusable within range	error
`V071`	COMPSys Fail out of Range	Compliance value unusable outside range	error
`V072`	COMPVHFail in Range	Vent hose compliance value unusable within range	error
`V073`	COMPVHFail out of Range	Vent hose compliance value unusable outside range	error
`value not stored`	O2 sensor calibration failed to store zero values	O2 zero calibration procedure failed	error
`WD00`	Watch dog time exp	Watchdog timer fired	critical

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.