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Circuit/System Testing

IMPORTANT: It is recommend that the defective components be replaced, and not the complete brake master cylinder assembly.
  1. Ignition OFF, disconnect the harness connector at the yaw rate/lateral and longitudinal accelerometer sensor.
  2. Test for less than 1 ohm between the ground circuit terminal 4 and ground.
    • If greater than the specified range, test for an open/high resistance in the ground circuit.
  3. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 1 and ground.
    • If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.
  4. Ignition OFF, disconnect the X2 harness connector at the EBCM.
  5. Ignition ON, test for 0 volts between the CAN HI circuit terminal 11 and ground.
    • If greater than the specified value, test the CAN HI circuit for a short to voltage.
  6. Test for 0 volts between the CAN LO circuit terminal 25 and ground.
    • If greater than the specified value, test the CAN LO circuit for a short to voltage.
  7. Ignition OFF, test for infinite resistance between the CAN HI circuit terminal 11 and ground.
    • If not the specified value, test the suspect circuit for a short to ground.
  8. Test for infinite resistance between the CAN LO circuit terminal 25 and ground.
    • If not the specified value, test the CAN LO circuit for a short to ground.
  9. Test for less than 1 ohm of resistance between the CAN HI circuit terminal 11 and terminal 2.
    • If greater than the specified range, test the CAN HI circuit for an open/high resistance.
  10. Test for less than 1 ohm of resistance between the CAN LO circuit terminal 3 and terminal 25.
    • If greater than the specified range, test the CAN LO circuit for an open/high resistance.
  11. Test for infinite resistance between the CAN HI terminal 11 and the CAN LO terminal 25.
    • If not the specified value, test the CAN HI and CAN LO circuits for a short together.
  12. If all circuits test normal, replace the Yaw Rate/Lateral sensor.
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