Description

Brake switch permanently active.

Effects on the driving operation

No retarder operation.

Possible causes

The brake switch has never been inactive in the current operating cycle although it can be assumed that the vehicle was not permanently braked.

Possible causes are:

- Defect at the brake switch that permanently causes a valid brake request.

- Defect in the vehicle cabling that permanently causes active brake requests.

Place of action

No description available.

Instruction

Check whether the brake switch provides a brake signal '0'.

With correct brake switch signal check whether the signals arrive correctly at the transmission control unit.

Setting conditions of the event

No description available.

Testing conditions of the event

No description available.

Final function check

If the defective component cannot be clearly identified, you should try to reproduce the fault:

• Reinstall the component in the vehicle.
• Test function.

After the fault has been eliminated, the following steps have to be carried out:

• Conduct a test drive with function check.
• Read the fault memory
• Check transmission for leaks.
• Perform a final visual inspection.

These steps are necessary to ensure the entire vehicle functions correctly.