Brake Lamp Switch - Jeep Wrangler TJ 2003 Service Manual

Symptom:

*BRAKE LAMP SWITCH

CHECK BRAKE LAMP SWITCH OUTPUT
BRAKE LAMP SWITCH B+ OPEN
BRAKE LAMP SWITCH OUTPUT CIRCUIT SHORT OR OPEN
BRAKE LAMP SWITCH OPEN
CAB -- INTERNAL OPEN
TEST
1 With the DRBIII in Inputs/Outputs, read the Brake Lamp Switch state.
Press and release the brake pedal.
Does the DRBIII display PRESSED and RELEASED?
Yes → The Brake Lamp Switch is OK.
→ Go To 2
No
2 Disconnect the Brake Lamp Switch harness connector.
Using a 12-volt test light connected to ground, check the Brake Lamp Switch Fused
B+ circuit.
Does the test light illuminate brightly ?
Yes → Go To 3
→ Repair the Brake Lamp Switch Fused B+ circuit for an open.
No
3 Disconnect the Brake Lamp Switch harness connector.
Connect a jumper wire between the Brake Lamp Switch B+ and Output circuits.
With the DRBIII in Inputs/Outputs, read the Brake Lamp Switch state.
Does the DRBIII display PRESSED?
Yes → Replace the Brake Lamp Switch in accordance with the Service
→ Go To 4
No
4 Disconnect the CAB harness connector.
Disconnect the Brake Lamp Switch harness connector.
Check the Brake Lamp Switch Output circuit for a short to voltage and an open.
Is the Brake Lamp Switch Output circuit shorted or open?
Yes → Repair the Brake Lamp Switch Output circuit for a short to
→ Replace the Controller Anti-Lock Brake in accordance with the
No
POSSIBLE CAUSES
ACTION
Perform ABS VERIFICATION TEST - VER 1.
Perform ABS VERIFICATION TEST - VER 1.
Information.
Perform ABS VERIFICATION TEST - VER 1.
voltage or an open.
Perform ABS VERIFICATION TEST - VER 1.
Service Information.
Perform ABS VERIFICATION TEST - VER 1.
37
BRAKES (CAB)
APPLICABILITY
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All
All
All