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Circuit/System Testing

NOTE:

It is recommended that Component Testing is performed before Circuit/System Testing when diagnosing the variable power steering solenoid valve.

  1. Ignition OFF, disconnect the harness connector at the M72 Variable Power Steering Solenoid Valve.
  2. Ignition ON, test for less than 0.3 V between the control terminals listed below and ground.
    • M72 Variable Power Steering Solenoid Valve, terminal A
    • M72 Variable Power Steering Solenoid Valve, terminal B
    • If greater than the specified value, test the control circuits for a short to voltage. If the circuits test normal, replace the K43 Power Steering Control Module.
  3. Ignition OFF, disconnect the negative terminal of the C1 Battery.
  4. Test for less than 10 Ω between the control circuit terminals listed below and ground.
    • M72 Variable Power Steering Solenoid Valve, terminal A
    • M72 Variable Power Steering Solenoid Valve, terminal B
    • If greater than the specified value, test the control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the K43 Power Steering Control Module.
  5. Disconnect the harness connector at the K43 Power Steering Control Module. Test for less than 2 Ω between the control circuit terminals listed below:
    • M72 Variable Power Steering Solenoid Valve, terminal A and K43 Power Steering Control Module, terminal 2
    • M72 Variable Power Steering Solenoid Valve, terminal B and K43 Power Steering Control Module, terminal 3
    • If greater than the specified value, test the control circuit for an open/high resistance.
  6. If all circuits test normal, test or replace the M72 Variable Power Steering Solenoid Valve.
  7. Clear the DTCs and operate the vehicle within the conditions for running the DTC. Verify DTC C0450 does not set.
    • If the DTC sets, replace the K43 Power Steering Control Module.