Pinpoint Test AJ: PSCM (Power Steering Control Module) DTC (Diagnostic Trouble Code) U0100:00

Refer to Power Steering Controls for schematic and connector information.

Normal Operation and Fault Conditions

Description

The PSCM monitors the HS-CAN messages when the ignition has been on for more than 5 seconds, the voltage to the PSCM is greater than 10 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.

Pinpoint Test Applicability

This test applies to PSCM DTC U0100 Lost Communication with the PCM only. It does not apply to any other module except the PSCM.

DTC Diagnostic Strategy

If the module DTC list results in a large number of Diagnostic Trouble Codes (DTCs), diagnose all module hard faults first (C102D, C1B00, C200B, C200C, C200D, U2011 and U3000) before diagnosing any network faults (lost communication or invalid data). If voltage concern Diagnostic Trouble Codes (DTCs) are present, diagnose those after any module hard faults and before any network faults. Diagnose all current and active Diagnostic Trouble Codes (DTCs) before diagnosing any historic Diagnostic Trouble Codes (DTCs).

Pinpoint Test Purpose

To verify the PSCM wiring harness and connectors are OK. This test checks the connectors and wiring from the PSCM 3-pin connector at the steering column to the in-line connector in the passenger compartment. If these circuits are working correctly, the test then directs to check the PCM and wiring harness.

Diagnostic Aids

For additional information on the messages sent to the PSCM from the PCM, refer to the Network Message List in Network Message Chart .
Do not install a new PSCM as part of the repair for a PSCM DTC U0100:00.

DTC Fault Trigger Conditions

DTC	Description	Fault Trigger Condition
PSCM U0100:00	Lost Communication With ECM/PCM "A": No Sub Type Information	This DTC sets if communications between the PSCM and the PCM fail. DTC U0100:00 can also be set due to a circuit fault in the HS-CAN, the PSCM wiring harness or a PCM concern.

Possible Sources