Circuit/System Testing
WARNING: This page is about a different car, the 2008 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the brake pedal position sensor.
- Ignition OFF, verify that a test lamp illuminates between B+ and the low reference circuit terminal A.
- If the test lamp does not illuminate, test the low reference circuit for an open/high resistance.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C and ground.
- If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the IPM.
- If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the IPM.
- Verify the scan tool BPP sensor parameter is less than 2 counts.
- If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the IPM.
- Install a 3A fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal C. Verify the scan tool BPP sensor parameter is greater than 1000 counts.
- If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the IPM.
- If all circuits test normal, test or replace the brake pedal position sensor.
C0277 09
- Replace the brake pedal position sensor.
- Perform the brake pedal position sensor recalibration procedure.
- Operate the vehicle within the Conditions for Running and Setting the DTC and verify the DTC does not reset.
- If the DTC resets, replace the IPM.