FixVault

Circuit/System Testing

  1. Ignition OFF, disconnect the X4 harness connector at the radio.
  2. Ignition ON, verify that a test lamp does not illuminate between the vehicle speed sensor signal circuit terminal 5 and ground.
    • If the test lamp illuminates, test the signal circuit for a short to voltage. If the circuit tests normal, replace the EBCM.
  3. Ignition OFF, verify that a test lamp illuminates between the vehicle speed sensor signal circuit terminal 5 and B+.
    • If the test lamp does not illuminate, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.
  4. Ignition OFF, disconnect the harness connector at the EBCM.
  5. Ignition OFF, verify that a test lamp does not illuminate between the vehicle speed sensor signal circuit terminal 3 and B+.
    • If the test lamp illuminates, test the signal circuit for a short to ground.
  6. If all circuits test normal, replace the radio.