Pinpoint Test Ag: PSCM (Power Steering Control Module) DTC (Diagnostic Trouble Code) U0401:00 Invalid Data Received From Powertrain Control Module
- Normal Operation and Fault Conditions
Description
- Description
- The PSCM monitors the HS-CAN messages when the voltage to the PSCM is greater than 10 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 PCM module, REFER to: Power Steering - System Operation and Component Description .
Pinpoint Test Applicability
- Pinpoint Test Applicability
- This test applies to PSCMDTC U0401 Invalid Data Received from the PCM only. It does not apply to any other module except the PSCM.
DTC Diagnostic Strategy
- 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
- Pinpoint Test Purpose
- To direct the diagnosis to the module and associated circuit sending the faulty or unknown information in the messages.
Diagnostic Aids
- Diagnostic Aids
- DTC U0401:00 indicates a concern with the PCM. The module reporting this DTC is not the problem module. Do not install a new PSCM as part of the repair for PSCMDTC U0401:00.
- When this DTC is set, steering assist is reduced resulting in higher steering efforts during low speed maneuvers.
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition PSCM U0401:00 Invalid Data Received from ECM/PCM A: No Sub Type Information The DTC sets when the PSCM receives invalid data from the PCM. The data is likely invalid due to PCM internal errors, damaged or inoperative sensors or components the PCM uses to gather vehicle data. The invalid data DTC is not set due to the PSCM, PSCM wiring or connectors. Possible Causes
- PCM sensors or components
- PCM
- AG1 CHECK THE PSCM DIAGNOSTIC TROUBLE CODES (DTCS)
- Start the vehicle.
- Using a diagnostic scan tool, carry out the PSCM self-test.
Is DTC U0401:xx currently present and active in the PSCM '
Yes GO to AG2 No If the scan tool cannot communicate with the PSCM, REFER to: Controller Area Network (CAN) Module Communications Network .
If the PSCM does NOT list DTC U0401:00 Invalid Data Received from Powertrain Control Module, DISCONTINUE this test and REFER to the DTC Chart for diagnostic direction. - AG2 CHECK THE VEHICLE BATTERY AND CHARGING SYSTEM VOLTAGE
- REFER to: Battery and carry out Pinpoint Test A: Battery Condition Test (battery state of charge).
Did the battery pass the condition test (battery state of charge)?
Yes GO to AG3 No INSTALL a new 12-volt battery. REFER to: Battery . GO to AG3 - AG3 RECHECK THE PSCM DIAGNOSTIC TROUBLE CODES (DTCS)
- Ignition ON.
- Using a diagnostic scan tool, clear the PSCM Diagnostic Trouble Codes (DTCs).
- Ignition OFF.
- Wait at least 1 minute for the module to power down.
- Start the engine.
- Using a diagnostic scan tool, carry out the PSCM self-test.
Is DTC U0401:xx currently present and active in the PSCM '
Yes DIAGNOSE the PCM concern. REFER to: Electronic Engine Controls . No The concern is not present at this time and may have been set due to a low battery state of charge. The test is complete, no further action is required.