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Circuit/System Testing

Brake Pedal Position Sensor Malfunction

  1. Ignition OFF, disconnect the harness connector at the B22 brake pedal position sensor.
  2. 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 K9 BCM.
  3. 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 K9 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 K9 BCM.
  4. Verify that the scan tool Brake Pedal Position Sensor parameter is less than 0.3 V.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
  5. Connect a 3 A fused jumper wire between the 5 V reference circuit terminal A and the signal circuit terminal B. Verify that the scan tool Brake Pedal Position Sensor parameter is 4.8-5.2 V.
    • If less than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the K9 BCM.
  6. If all circuits test normal, test or replace the B22 brake pedal position sensor.

Stop Lamp Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate E5 tail/stop lamp.
  2. Test for less than 5 Ω between the ground circuit terminal 1 and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal C and ground.
  4. 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 K9 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 K9 BCM.
  5. If all circuits test normal, test or replace the E5 tail/stop lamp.

Center High Mounted Stop Lamp Malfunction

  1. Ignition OFF, disconnect the harness connector at the E6 center high mounted stop lamp.
  2. 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.
  3. Connect a test lamp between the control circuit terminal 2 and ground.
  4. 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 K9 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 K9 BCM.
  5. If all circuits test normal, test or replace the E6 center high mounted stop lamp.