Signal Too High

Signal too high

Checking the status




- Ignition on.
Check the twilight sensor signal by varying the intensity of the light that it detects. Cover the twilight sensor with your hand to obtain the minimum signal, approximately 0.5 volts.
Then aim a strong light source (for example a flashlight) at the twilight sensor from close range to increase the signal.

Hint: If the signal from the twilight sensor indicates >4.75 volts, there is either an open-circuit in the cable or the twilight sensor is defective.

Click on the VCT2000 symbol to read off the light intensity (voltage).

Note! The illustration only shows the method. The appearance of the twilight sensor can vary between different models.









Continue - Checking the component and wiring

-------------------------------------------------

Checking the component and wiring
Check the signal cable between central electronic module (CEM) terminal #B29 (#29) and twilight sensor connector terminal #4. Check for an open-circuit. Check for a short-circuit to supply voltage.
Check the ground lead between central electronic module (CEM) terminal #B28 (#28) and twilight sensor connector terminal #5. Check for an open-circuit. Check for a short-circuit to supply voltage.
Replace the twilight sensor if no fault is found in the wiring.
Remedy as necessary.

Other information
- Connecting the breakout box Connecting the Breakout Box, Central Electronic Module (CEM)
- Signal specification Signal Description, Central Electronic Module (CEM)
- Control module relay box passenger compartment Service and Repair
- Sun sensor Service and Repair
- Checking wiring and terminals Checking Wiring and Terminals













Continue - 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 the twilight sensor signal by varying the light intensity at the twilight sensor. Cover the twilight sensor with your hand to reduce the signal. Then aim a strong light source (for example a flashlight) at the twilight sensor from close range to obtain the maximum signal.
The value should vary between approximately 0.5 and 4.75 volts.









Is the function OK?

Yes - Troubleshooting procedure complete

No - Fault-tracing information

-------------------------------------------------

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

------------------------

Attempt New Test - Checking the component and wiring

-------------------------------------------------