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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the yaw rate/lateral acceleration sensor.
  2. Ignition OFF for 60 seconds, test for less than 5 ohms between the low reference circuit terminal 1 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 yaw rate/lateral acceleration sensor.
  3. Ignition ON, test for ignition voltage between the ignition voltage circuit terminal 4 and ground.
    • If not within the specified range, test the ignition voltage circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the yaw rate/lateral acceleration sensor.
  4. Ignition OFF, disconnect the harness connector X3 at the SCM, and X3 at the EBCM.
  5. Ignition ON, test for less than 1 volt between the following terminal listed below and ground.
    • SCM serial data circuit terminal 52
    • SCM serial data circuit terminal 72
    • If greater than the specified value, test the appropriate serial data circuit for a short to voltage. If the circuit tests normal, replace the yaw rate/lateral acceleration sensor.
  6. Ignition OFF, test for infinite resistance between the following terminal listed below and ground.
    • SCM serial data circuit terminal 52
    • SCM serial data circuit terminal 72
    • If not the specified value, test the appropriate serial data circuit for a short to ground. If the circuit tests normal, test or replace the yaw rate/lateral acceleration sensor
  7. Test for less than 2 ohms between the appropriate serial data circuit terminals listed below.
    • Serial data circuit terminal 52 at the SCM harness connector and terminal 2 at the yaw rate/lateral acceleration sensor harness connector.
    • Serial data circuit terminal 72 at the SCM harness connector and terminal 3 at the yaw rate/lateral acceleration sensor harness connector.
    • If greater than the specified range, test the appropriate serial data circuit for an open/high resistance. If the circuit tests normal, replace the yaw rate/lateral acceleration sensor.
  8. Test for infinite resistance between the SCM serial data circuit terminal 52 and the SCM serial data circuit terminal 72.
    • If not the specified value, repair the serial data circuits for a short together.
  9. If all circuits test normal, replace the SCM.
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