Faulty Signal

Faulty signal

Checking combustion fan function




- Ignition on.
- Activate combustion fan.
Listen for a buzzing sound which indicates that the combustion fan is running.





Does the combustion fan function?

Yes - Intermittent fault

No - Checking the connectors

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Checking the connectors








- Ignition off.
- Remedy combustion fan electrical terminals and control module connector for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Check any damage etc.
- Reinstall components, reconnect connectors etc.
- Ignition on.
- Activate combustion fan.
Listen for a buzzing sound which indicates that the combustion fan is running.
If the combustion fan now operates it means that the cause of the fault has been loose connections in the connectors.

Other information:
- To access the control module/connect breakout box see.
- To access the combustion fan, position heater in service mode according to Moving the heater to its service position Procedures and remove fan shroud.





Does the combustion fan function?

Yes - FAULT FOUND

No - Replacing component

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Replacing component
- Ignition off.
Try a new combustion fan according to Replacing fuel injection nozzle, fan motor and nozzle pipe Service and Repair.

Continue - Verification

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Verification




Verification

Hint: After carrying out the repair, check that the fault has been remedied.








- Ignition off.
- Reinstall connectors, components etc.
- Ignition on.
- Activate combustion fan.
Listen for a buzzing sound which indicates that the combustion fan is running.





Does the combustion fan function?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFICATION FAILED - Fault-tracing information

VERIFIED - FAULT FOUND

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Fault-tracing information




Information

Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.

Do you want to exit fault-tracing?

Yes - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking combustion fan function

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Intermittent fault
- Ignition off.
Check combustion fan electrical terminals and control module connector for contact resistance and oxidation according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.

Other information:
- To access the control module/connect breakout box see.
- To access the combustion fan, position heater in service mode according to Moving the heater to its service position Procedures and remove fan shroud.









Continue - Fault-tracing information
DONE

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Fault-tracing information




Information

Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.
It is possible to view the information again, or leave fault-tracing for this diagnostic trouble code (DTC).

Do you want to view the information again?

Yes - Attempt New Test

No - FAULT FOUND

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Attempt New Test - Checking combustion fan function

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