Pinpoint Test I: The Power Steering Control Module (PSCM) Does Not Respond To The Scan Tool

Communications Network

Pinpoint Test I: The Power Steering Control Module (PSCM) Does Not Respond To The Scan Tool

Refer to Wiring Diagram Set 14, Module Communications Network for schematic and connector information Electrical Diagrams.

Refer to Wiring Diagram Set 43, Power Steering Controls for schematic and connector information Electrical Diagrams.

Normal Operation

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

This pinpoint test is intended to diagnose the following:

- Fuse

- Wiring, terminals or connectors

- PSCM (Power Steering Control Module)

PINPOINT TEST I : THE PSCM (Power Steering Control Module) DOES NOT RESPOND TO THE SCAN TOOL

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings.

I1 CHECK THE PSCM (Power Steering Control Module) VOLTAGE SUPPLY CIRCUITS FOR AN OPEN

- Ignition OFF.

- Disconnect: PSCM (Power Steering Control Module) C2368A and C2368B.

- Ignition ON.

- Measure the voltage between the PSCM (Power Steering Control Module) C2368A-1, circuit SBF02 (YE/RD) harness side and ground.





- Measure the voltage between the PSCM (Power Steering Control Module) C2368B-5, circuit CBP21 (BU/GY) harness side and ground.





Is the voltage greater than 10 volts?

Yes
GO to I2.

No
VERIFY the Battery Junction Box (BJB) fuse mega 2 (60A) and Central Junction Box (CJB) fuse 21 (10A) is OK. If OK, REPAIR the circuit in question. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short Electrical Diagrams. CLEAR the DTCs. REPEAT the network test with the scan tool.

I2 CHECK THE PSCM (Power Steering Control Module) GROUND CIRCUITS FOR AN OPEN

- Ignition OFF.

- Disconnect: Negative Battery Cable.

- Disconnect: PSCM (Power Steering Control Module) C2368C.

- Measure the resistance between the PSCM (Power Steering Control Module) C2368C-1, circuit GD120 (BK/GN), harness side and ground.





Is the resistance less than 5 ohms?

Yes
GO to I3.

No
REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.

I3 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

- Measure the resistance between the PSCM (Power Steering Control Module) C2368B-2, circuit VDB04 (WH/BU), harness side and the DLC (Data Link Connector) C251-6, circuit VDB04 (WH/BU), harness side.





- Measure the resistance between the PSCM (Power Steering Control Module) C2368B-6, circuit VDB05 (WH), harness side and the DLC (Data Link Connector) C251-14, circuit VDB05 (WH), harness side.





Are the resistances less than 5 ohms?

Yes
CONNECT the negative battery cable. GO to I4.

No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.

I4 CHECK FOR CORRECT PSCM (Power Steering Control Module) OPERATION

- Disconnect the PSCM (Power Steering Control Module) connector.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect the PSCM (Power Steering Control Module) connector and make sure it seats correctly.

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

Is the concern still present?

Yes
INSTALL a new PSCM (Power Steering Control Module). CLEAR the DTCs. REPEAT the network test with the scan tool.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.