Signal Missing

Signal missing

Checking the cable and component








- Ignition off
- Check the connectors for the upper electronic module (UEM) and roof lamp module. Check for contact resistance and oxidation.
Remedy as necessary
- Reinstall the connectors, components etc.
- Ignition on.
Activate the general lighting: Click on the VCT2000 symbol.

Other information:
- To access the roof lamp switch, see Replacing interior lighting Service and Repair
- To access the connector for the upper electronic module (UEM), see Upper electronic module (UEM) rear view / door mirror, replacing Service and Repair
- Checking wiring and terminals Checking Wiring And Terminals.









Do the lamps light?

Yes - Verification

No - Checking for an open-circuit

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Checking for an open-circuit
Check the cable between the control module terminal #19 and roof lamp module terminal #5A. Check for an open-circuit. Check for a short-circuit to supply voltage.
Replace the cable if a fault is found.
If no fault was found, try replacing the lamps.

Other information:
- For further information about signals and other values, see Signal specification Signal Specification, Upper Electronic Module (UEM)
- To connect the breakout box, see Connecting the breakout box Connecting the Breakout Box
- To replace the lamps, see Replacing interior lighting Service and Repair
- Checking wiring and terminals Checking Wiring And Terminals.










Continue - Verification

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Verification




Verification

Verification

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








- Ignition off.
- Reinstall the connectors, components etc.
- Ignition on.
Check that the relevant lamp button and lamp are functioning.

Does the lamp function?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFIED - Fault Found

VERIFICATION FAILED - Fault-tracing information

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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 - FAULT-TRACING FAILED

No - Attempt New Test

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Attempt New Test - Checking the cable and component

FAULT-TRACING FAILED - No Fault Found

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