The power steering control module (PSCM) continuously monitors the voltage and current levels being commanded to the electric power steering (EPS) motor. A DC/DC converter is applied to the battery voltage input to the PSCM to boost the pulse width modulated (PWM) command circuit to drive the brushless, 3 phase motor. The PSCM compares the desired and actual current levels to detect malfunctions in the EPS motor, or the circuits to the motor.

The ignition is ON.

The PSCM detects open, short to ground or short between any of the motor phase circuits.

Schematic Reference:

Power Steering Schematics

Connector End View Reference:

Power Steering Connector End Views

Description and Operation:

Power Steering System Description and Operation

Electrical Information Reference:

Scan Tool Reference:

Ignition ON, turn the steering wheel left and right. Verify that DTC C0475 does not set.

1. Ignition OFF, disconnect the harness connector C1 at the PSCM.
2. Ignition OFF, test for less than 1.0 ohm of resistance between the U phase circuit terminal 2 and the V phase circuit terminal 3 of the power steering motor.

⇒	If greater than the specified range, test the U and V phase circuits for an open/high resistance. If circuits test normal, replace the power steering motor.

3. Ignition OFF, test for less than 1.0 ohm of resistance between the V phase circuit terminal 3 and the W phase circuit terminal 1 of the power steering motor.

⇒	If greater than the specified range, test the V and W phase circuits for an open/high resistance. If circuits test normal, replace the power steering motor.

4. Ignition OFF, test for less than 1.0 ohm of resistance between the U phase circuit terminal 2 and the W phase circuit terminal 1 of the power steering motor.

⇒	If greater than the specified range, test the U and W phase circuits for an open/high resistance. If circuits test normal, replace the power steering motor.

5. Ignition OFF, test for greater than 1.0 Mega-ohm of resistance between the U phase circuit terminal 2 and ground.

⇒	If less than the specified range, test the U phase circuit for a short to ground. If circuits test normal, replace the power steering motor.

6. Ignition OFF, test for greater than 1.0 Mega-ohm of resistance between the V phase circuit terminal 3 and ground.

⇒	If less than the specified range, test the V phase circuit for a short to ground. If circuits test normal, replace the power steering motor.

7. Ignition OFF, test for greater than 1.0 Mega-ohm of resistance between the W phase circuit terminal 1 and ground.

⇒	If less than the specified range, test the W phase circuit for a short to ground. If circuits test normal, replace the power steering motor.

8. If all circuits test normal, test or replace the PSCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.