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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the steering angle sensor.
  2. Ignition OFF for 60 seconds, test for less than 5 ohms between the low reference circuit terminal 6 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 SAS.
  3. Ignition ON, test for ignition voltage between the ignition voltage circuit terminal 5 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 SAS.
  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, test or replace the steering angle 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 steering angle 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 1 at the steering angle sensor harness connector.
    • Serial data circuit terminal 72 at the SCM harness connector and terminal 3 at the steering angle 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 steering angle 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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