Circuit Description
The body control module (BCM) receives a signal from the brake pedal position sensor through the brake position sensor signal circuit. The BCM then applies a signal through the stop lamp switch signal circuit to the power control module (PCM).
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0572 Cruise Control Brake Switch Circuit Low Voltage
Conditions for Running the DTC
| • | The 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 PCM detects voltage on the stop lamp switch signal circuit when the circuit should be open.
Action Taken When the DTC Sets
| • | The PCM stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The PCM records the operating conditions at the time the diagnostic fails. The PCM 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 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
.
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 | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
Does the Stop Lamp Pedal Switch parameter indicate Applied? | 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 battery positive voltage in the stop lamp switch signal circuit. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 7 | Go to Step 5 |
5 | Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the repair? | Go to Step 7 | -- |
6 | Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 7 | -- |
7 |
Does the DTC reset? | Go to Step 2 | System OK |
