Circuit Description
The Stoplamp Switch is a normally open switch, when the brake pedal is depressed the EBCM will sense battery voltage. This allows the EBCM to determine the state of the brake lamps.
Conditions for Setting the DTC
| • | EBCM detects battery voltage at all times. |
| • | EBCM never detects battery voltage from CKT 20. |
| • | Both brake lamps are faulty. |
Action Taken When the DTC Sets
| • | DTC C0161 is set. |
| • | ABS and TCS remains active. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used. |
| • | 100 ignition cycles pass with no DTCs detected. |
Diagnostic Aids
| • | It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction. |
| • | Thoroughly inspect any circuitry that may be causing the complaint for the following conditions: |
| - | Backed out terminals |
| - | Improper mating |
| - | Broken locks |
| - | Improperly formed or damaged terminals |
| - | Poor terminal-to-wiring connections |
| - | Physical damage to the wiring harness |
| • | The following conditions may cause an intermittent malfunction: |
| - | A poor connection |
| - | Rubbed-through wire insulation |
| - | A broken wire inside the insulation |
| • | If an intermittent malfunction exists refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the Diagnostic System Check performed? | -- | ||
2 | Observe the rear brake lamps. Are the brake lamps off? | -- | ||
3 | Disconnect the Stoplamp Switch connector C1. Are the brake lamps on? | -- | ||
4 | Press the brake pedal. Do the brake lights come on? | -- | ||
Is the voltage within specifications? | B+ | |||
6 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Is the replacement complete? | -- | -- | |
7 | Repair the open or high resistance in CKT 20. Refer to Wiring Repairs . Is the circuit repair complete? | -- | -- | |
8 | Check the STOP/HAZARD fuse in the I/P Fuse Block. Is the fuse OK? | -- | ||
9 |
Is the voltage within specifications? | B+ | ||
10 | Repair the open in CKT 140. Refer to Wiring Repairs . Is the circuit repair complete? | -- | -- | |
Connect a fused jumper wire between the Stoplamp Switch harness connector terminals A and B. Do the brake lamps come on? | -- | |||
12 | Adjust or repair the Stoplamp Switch as necessary. Is the repair complete? | -- | -- | |
13 |
Is the fuse OK? | -- | ||
14 | Repair the short to ground in CKT 140. Refer to Wiring Repairs . Is the circuit repair complete? | -- | -- | |
15 |
Is the fuse OK? | -- | ||
16 |
Is the fuse OK? | -- | ||
17 | Repair the short to ground in CKT 20. Refer to Wiring Repairs . Is the circuit repair complete? | -- | -- | |
18 | Repair CKT 20 for a short to voltage. Refer to Wiring Repairs . Is the repair complete? | -- | -- |
