Faulty Signal. Permanent Fault
Faulty signal. Permanent fault
Information
The brake control module diagnoses the stop lamp switch by comparing the signals from the stop lamp switch with the signal from the pedal position sensor. In certain cases the control module cannot determine if the fault is in the circuit for the stop lamp switch or in the circuit for the pedal position sensor. The pedal position sensor is diagnosed by the engine control module (ECM).
If diagnostic trouble codes (DTCs) for the pedal position sensor are stored in the engine control module (ECM) select Cancel and Fault-trace according to the accompanying information.
Continue - Checking the control module and wheel sensor connectors
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Checking the control module and wheel sensor connectors
- Ignition off
- Check the ABS control module and stop lamp switch connectors for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault
- Reinstall the components, reconnect the connectors etc.
- Ignition on
- Read off the status of the stop lamp switch.
Depress and release the brake pedal. The value must change between OFF and ON.
If the value changes, the cause of the fault was loose connections in the control module or wheel sensor connectors.
Other information:
- For information about removing the ABS control module connector, see Control module (ABS), replacing Brake Control Module (BCM), Replacing.
Does the value change?
Yes - Fault Found
No - wiring and sensors
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Checking the fuse, wiring and sensors
Check that fuse 2 in the integrated relay / fusebox in the engine compartment is intact. Check the cable between stop lamp switch terminal #1 and fuse 11/2 in the integrated relay / fusebox in the engine compartment and between stop lamp switch terminal #2 and splice 53/365. Check for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. Check for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. Check for a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Check the cables between splice 53/365 and central electronic module (CEM) terminal #B4 and between splice 53/365 and engine control module (ECM) terminal #B26. Check for an open-circuit. See Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. Check for a short-circuit to ground. See Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. Check for a short-circuit to supply voltage. See Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Hint: Check the stop lamp switch by measuring the resistance between terminals #1 and #2 on the stop lamp switch. When the brake pedal is not depressed the resistance should be infinite. When the brake pedal is depressed the resistance should be 0 ohms.
Remedy as necessary.
Other information:
- To connect the breakout box to the ABS control module, see Connecting the ABS breakout box Pinout Values and Diagnostic Parameters
- To connect the breakout box to the engine control module (ECM), see Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box
- To connect the breakout box to the central electronic module, see Connecting the breakout box Connecting the Breakout Box, Central Electronic Module (CEM)
- To replace the stop lamp switch, see Stop lamp switch, replacing Service and Repair.
Was a fault detected?
Yes - Verification
No - FAULT-TRACING FAILED
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Verification
- Ignition off
- Reinstall the components, reconnect the connectors etc.
- Ignition on
- Read off the status of the stop lamp switch.
Depress and release the brake pedal. The value must change between OFF and ON.
Does the value change?
Yes - VERIFIED
No - 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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FAULT-TRACING FAILED - FAULT-TRACING FAILED
Attempt New Test - Information
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