P1576

BRAKE LIGHT SWITCH





Symptom Of Fault.
The CHECK ENGINE lamp (MIL) is on.
Only basic boost pressure.

Conditions.
Engine running.
Braking 6 times from 22 to 0 mph (35 to 0 km/h).
Each brake application shorter than 10 seconds.
No status change on the input from the brake light switch.
P1576: Short circuit to battery positive (B+).
P1577: Short circuit to ground/open circuit

Diagnostic Help.
The status ("ON/OFF") of the brake light switch can be ascertained by means of the ISAT scan tool.
- Select "ON/OFF".
- Select "BRAKE LIGHT SWITCH".





Diagnostic Procedure.
1 Check the brake lights

- Check whether the brake lights come on when the brake pedal is depressed.

Do the brake lights work?

YES: Check the lead between pin 15 of the control module and crimped connection J32. Repair or replace the lead if necessary. Continue with point 2.

NO: Continue fault diagnosis in the electrical system, brake lights.
Then carry out a final check in accordance with point 2.

2 Final check:

- Clear the diagnostic trouble code.
- Implementation of driving cycle:
Drive the car at varying engine loads and rpm for 5 minutes.
- Evaluation of driving cycle:
- Connect an ISAT scan tool.
- Select "READ ON/OFF".
- Select "BRAKE LIGHT SWITCH". The ISAT scan tool display should read "ON" when the brake pedal is depressed.

Does the display read "OFF"?
YES: Proceed at "Before Replacing A Control Module". Component Tests and General Diagnostics

NO: The remedial measure taken was correct.