Circuit/System Testing
Brake Pedal Position Sensor Malfunction
- Ignition OFF, disconnect the harness connector at the brake pedal position sensor.
- Ignition OFF, test for less than 5 Ω between the low reference circuit terminal C and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
- Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal A and ground.
- If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
- If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the BCM.
- Test for less than 0.3 V between the signal circuit terminal B and ground.
- If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.
- Test for 4.8-5.2 V between the 5 V reference circuit terminal A and the signal circuit terminal B.
- If less than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
- If all circuits test normal, test or replace the brake pedal position sensor.
Stop Lamp Malfunction
- Ignition OFF, disconnect the harness connector at the appropriate tail lamp.
- Test for less than 5.0 Ω between the ground circuit terminal listed below and ground:
- With RPO Z88 - terminal D
- Without RPO Z88 - terminal B
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Connect a test lamp between the control circuit terminal listed below and ground:
- With RPO Z88 - terminal E
- Without RPO Z88 - terminal A
- Ignition ON, press and release the brake pedal. The test lamp should turn ON and OFF when changing between the selected states.
- If the test lamp is always ON, test the control circuit for a short to voltage.
- If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance.
- If all circuits test normal, test or replace the tail lamp.
Center High Mount Stop Lamp Malfunction
- Ignition OFF, disconnect the harness connector at the center high mounted stop lamp.
- Test for less than 5 Ω between the ground circuit terminal 1 and ground.
- If greater than the specified value, test the ground circuit for an open/high resistance.
- Connect a test lamp between the control circuit terminal 2 and ground.
- Ignition ON, press and release the brake pedal. The test lamp should turn ON and OFF when changing between the selected states.
- If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
- If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
- If all circuits test normal, test or replace the center high mounted stop lamp.