Pinpoint Test Al: PSCM (Power Steering Control Module) DTC (Diagnostic Trouble Code) U0140:00 Lost Communication With Body Control Module
WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Refer to Steering GSB for additional connector and wiring inspection tips.
Refer to Wiring Diagrams POWER STEERING CONTROLS for schematic and connector information.
Normal Operation and Fault Conditions
Description
- The PSCM monitors the HS-CAN messages when the voltage to the PSCM is greater than 9 volts and there are no Diagnostic Trouble Codes (DTCs) present inhibiting PSCM operation.
- For additional information on the messages sent to the PSCM from the BCM module, REFER to: Power Steering - System Operation and Component Description .
Pinpoint Test Applicability
- This test applies to PSCMDTC U0140 Lost Communication with the BCM 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 gear to the in-line connector in the engine compartment. If these circuits are working correctly, the test then directs to check the BCM and wiring harness.
Diagnostic Aids
- Do not install a new PSCM as part of the repair for a PSCMDTC U140:00.
- DTC U0140:00 indicates a possible failure of the HS-CAN, the PSCM wiring harness or a BCM concern.
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Condition |
|---|---|---|
| PSCM U0140:00 | Lost Communication With Body Control Module: No Sub Type Information | This DTC sets when the PSCM does not receive the BCM messages within a certain time frame. This can occur if the BCM wiring harness or electrical connectors are loose or damaged, or if the vehicle battery state of charge levels are low. |
Possible Sources
- Fuse(s)
- Wiring, terminals or connectors
- Network communication concern
- BCM
Pinpoint Tests AL: PSCM DTC U0140 Lost Communication With The BCM