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Signal Outside Its Permitted Range






Signal outside its permitted range

Checking the control module and wheel sensor connectors








- Ignition off
- Check the brake control module (BCM) and stop (brake) lamp switch connectors. Check for contact resistance and oxidation
- 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 brake control module (BCM) connector, see Connecting the breakout box, brake control module (BCM) Connecting the Breakout Box, Brake Control Module (BCM)
- To fault-trace the wiring and connections, see Checking wiring and terminals Checking Wiring And Terminals.





Does the value change?

Yes - Fault Found

No - wiring and sensors

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Checking the fuse, wiring and sensors
Check that the fuse for the stop (brake) lamp switch in the integrated relay / fusebox in the engine compartment is intact.
Check the cable between stop lamp switch terminal #1 and the fuse in the integrated relay / fusebox in the engine compartment and between stop lamp switch terminal #5 and the splice. Check for an open-circuit. Check for a short-circuit to ground. Check for a short-circuit to supply voltage.
Check the cable between the splice and central electronic module (CEM) terminal #B4 and between the splice and engine control module (ECM) terminal #B26. Check for an open-circuit. Check for a short-circuit to ground. Check for a short-circuit to supply voltage.

Hint: Check the stop lamp switch by measuring the resistance between terminals #1 and #5 on the stop lamp switch. When the brake pedal is depressed the resistance should be infinite. When the brake pedal is not depressed the resistance should be 0 ohms.

Remedy as necessary.

Other information
- To connect the breakout box to the brake control module (BCM), see Connecting the breakout box, brake control module (BCM) Connecting the Breakout Box, Brake Control Module (BCM)
- To connect the breakout box to the Engine control module (ECM), see: Connecting the breakout box, B5244T5, B5254T2 Connecting the Breakout Box
- For connection of breakout box to central electronic module (CEM), 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
- Checking wiring and terminals Checking Wiring And Terminals
- For further information about the locations of fuses and relays, see the Wiring Diagram.









Was a fault detected?

Yes - Verification

No - No Fault Found

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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 - Fault Found

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 - Checking the control module and wheel sensor connectors

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