Signal Missing

Signal missing

Checking the power supply and ground terminal




- Ignition off.
Check that the fuse for internal rearview mirror on the central electronic module (CEM) is intact. If the fuse is blown, check the subsequent circuit for a short-circuit to ground. Then replace the fuse.
Check cable for power supply between inner rearview mirror #A3 and Central electronic module (CEM) #H 4 (#18) for open circuit.
Check cable for ground between inner rearview mirror #A1 and Central electronic module (CEM) #D12 (#12) for open circuit.
Check the signal line between inner rearview mirror #A2 and Central electronic module (CEM) #H23 (#37) for open circuit as well as short-circuiting to voltage.
Remedy the cables as necessary.
Switch on the ignition. Check that the relay for extended X-supply is activated.
Click the VCT2000 symbol to read the relay status.

Other information
- Connecting the breakout box Connecting the Breakout Box, Central Electronic Module (CEM)

- Checking wiring and terminals Checking Wiring and Terminals









Was a fault detected?

Yes - Verification

No - Checking communication

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Checking communication




- Ignition on.
Check that communication with humidity sensor (HUS) works, by reading out the value in question.
Click the symbol for VCT2000 to begin reading off.





Does the sensor respond?

Yes - DONE

No - Replacing the control module

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Replacing the control module




- Ignition off.
If no problem is detected on the leads to the internal rearview mirror, it needs to be replaced.

Other information
Inner rear view mirror Inner Rear View Mirror

Continue - Verification

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Fault-tracing information

Attempt New Test - Checking the power supply and ground terminal

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Verification




- Ignition off
- Reconnect cables and switches
- Ignition on.
Check that communication with humidity sensor (HUS) works, by reading out the value in question.
Click the symbol for VCT2000 to begin reading off.





Does the sensor respond?

Yes - FAULT FOUND

No - Fault-tracing information

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