Diagnostic Routine AC

Diagnostic Routine AC

Diagnostic Overview

The Power Steering Control Module (PSCM) Does Not Respond To The Scan Tool

Refer to Wiring Diagram Set 14 for schematic and connector information Electrical Diagrams.

Refer to Wiring Diagram Set 43 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

The PSCM (Power Steering Control Module) communicates with the scan tool through the HS-CAN (High Speed Controller Area Network).

Visual Inspection and Diagnostic Pre-checks

Verify BJB (Battery Junction Box) fuse 89 (5A) is OK.

Pinpoint Test

1. CHECK THE PSCM (Power Steering Control Module) VOLTAGE SUPPLY CIRCUITS FOR AN OPEN

1. Ignition OFF.

2. Disconnect: PSCM (Power Steering Control Module) C1463A.

3. Ignition ON.

4. Measure:





Is the voltage greater than 11 volts?






2. CHECK THE PSCM (Power Steering Control Module) GROUND CIRCUIT FOR AN OPEN

1. Ignition OFF.

2. Disconnect: PSCM (Power Steering Control Module) C1463B.

3. Measure:





Is the resistance less than 3 ohms?






3. CHECK THE HS-CAN (High Speed Controller Area Network) CIRCUITS BETWEEN THE PSCM (Power Steering Control Module) AND THE DLC (Data Link Connector) FOR AN OPEN

1. Measure:





Are the resistances less than 3 ohms?






4. CHECK FOR CORRECT PSCM (Power Steering Control Module) OPERATION

1. Ignition OFF.

2. Disconnect and inspect the PSCM (Power Steering Control Module) connectors.

3. Repair:

- corrosion (replace connector or terminals- clean module pins)
- damaged or bent pins- replace terminals/pins
- pushed-out pins- replace pins as necessary

4. Reconnect the PSCM (Power Steering Control Module) connectors. Make sure they seat and latch correctly.

5. Operate the system and verify the concern is still present.

Is the concern still present?