Circuit Description
The body control module (BCM) receives a signal from the brake pedal position sensor through the brake pedal sensor signal circuit. The BCM then applies voltage through the stop lamp switch signal circuit to the transmission control module (TCM) and engine control module (ECM).
Conditions for Running the DTC
| • | Vehicle has cycled from 0-60 km/h (0-37 mph) 3 times in 1 ignition cycle. |
| • | Continuous once the previous criteria have been met. |
Conditions for Setting the DTC
The TCM detects an open or short to ground on the stop lamp switch signal circuit when the voltage should be present.
Action Taken When the DTC Sets
| • | The TCM stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The TCM records the operating conditions at the time the diagnostic fails. The TCM stores this information in the Failure Records. |
Conditions for Clearing the DTC
| • | A last test failed, or current DTC, clears when the diagnostic runs and does not fail. |
| • | A history DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic. |
| • | Use a scan tool in order to clear the DTC. |
Diagnostic Aids
Important:
• Verify that the brake pedal position sensor switch is adjusted properly.
Refer to
Brake Pedal Position Sensor Calibration
. • Test drive the vehicle if a switch or circuit condition cannot be located.
An intermittent condition may be duplicated during a test drive. • For an intermittent, refer to
Testing for Intermittent Conditions and Poor Connections
in Wiring Systems.
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Exterior Lights Schematics Connector End View Reference: Master Electrical Component List in Wiring Systems | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
Does the Stop Lamp Pedal Switch parameter indicate Unapplied? | Go to Step 3 | Go to Diagnostic Aids | |
3 |
Does the test lamp illuminate? | Go to Step 4 | Go to Step 6 |
4 | Test for a short to ground, an open or a poor connection in the stop lamp switch signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 7 | Go to Step 5 |
5 | Replace the transmission control module (TCM). Refer to Transmission Control Module Replacement in Automatic Transmission - 5L50-E. Did you complete the repair? | Go to Step 7 | -- |
6 |
Important: After replacing the BCM, perform the setup procedure. Refer to Body Control Module (BCM) Programming/RPO Configuration in Computer/Integrating Systems. Replace the BCM. Refer to Body Control Module Replacement in Computer/Integrating Systems. Did you complete the replacement? | Go to Step 7 | -- |
7 |
Does the DTC reset? | Go to Step 2 | System OK |
