Diagnostic trouble codes P1576,P1577
|
|
Diagnostic trouble codes P1576,
P1577
|
Brake light switch
Symptom of fault
The CHECK ENGINE lamp (MIL) is on. Only basic boost pressure.
Conditions
Engine running. Braking 6 times from 35 km/h to 0 km/h. Each braking manoeuvre
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
"BRAKE LIGHT SWITCH".
|
Checking the wiring. Intermittent faults may occur as a result of occasional short
circuits and breaks in the wiring. Jiggle the leads and in-line connectors at several places and
in different directions to reveal faults in the wiring harness. Observe the multimeter, ISAT scan
tool or test lamp while carrying out this check.
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?
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.
Continue fault diagnosis as described in Service Manual 3:2 "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
"BRAKE LIGHT SWITCH".
|
The ISAT scan tool display should read "ON" when the brake pedal is
depressed.
Does the display read "OFF"?
Proceed to
.
The remedial measure taken was correct.
