Circuit Description
The EBCM uses this stoplamp switch circuit for various performance measures within ABS/TCS/VSES. This DTC is set if the EBCM has determined that the stoplamp switch is continously ON. The TCS cannot be activated when the stoplamp switch is ON
Conditions for Running the DTC
The vehicle speed is greater than 40 km/h (25 mph).
Conditions for Setting the DTC
The stop lamp switch input was active for 2 consecutive ignition cycles.
Action Taken When the DTC Sets
| • | The EBCM disables the TCS for the duration of the ignition cycle. |
| • | The TRACTION CONTROL indicator turns ON. |
| • | The ABS remains functional. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present (the DTC is not current) and you used the scan tool Clear DTC function. |
| • | The condition for the DTC is no longer present (the DTC is not current) and you used the On-Board Diagnostics Clear DTC function. |
| • | The EBCM automatically clears the history DTC when a current DTC is not detected in 50 consecutive drive cycles. |
Diagnostic Aids
Possible causes of this DTC are the following conditions:
| • | The stop lamp switch circuit is shorted to voltage. |
| • | The stop lamp switch is misadjusted. |
| • | The stop lamp switch is stuck closed. |
| • | A brake pedal that is binding. |
| • | Both brake light bulbs are burned out. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the ABS Diagnostic System Check? | -- | Go to Step 2 | |
Does the scan tool display Released? | -- | Go to Step 3 | Go to Step 4 | |
3 |
Does the Brake Light Switch parameter change state? | -- | Go to Diagnostic Aids | Go to Step 4 |
4 |
Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 5 |
5 |
Does the scan tool display Released? | -- | Go to Step 8 | Go to Step 6 |
6 | Test the signal circuit of the stoplamp/AT shift lock control switch for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 7 |
7 | Inspect for poor connections at the harness connector of the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 9 |
8 | Inspect for poor connections at the harness connector of the stoplamp/AT shift lock control switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 10 |
9 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Did you complete the replacement? | -- | Go to Step 11 | -- |
10 | Replace the stoplamp/AT shift lock control switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes. Did you complete the replacement? | -- | Go to Step 11 | -- |
11 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
