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DTC U0401:00 [ELECTRIC POWER STEERING (EPS)]

id0602a1812200

Outline

System malfunction location

Signal error from PCM

Detection condition

•  Error detected in signal from PCM via CAN communication

Fail-safe

•  Refer to “Fail-safe Function Table”.(See DTC TABLE [ELECTRIC POWER STEERING (EPS) (E)].)

Possible cause

•  PCM malfunction

System wiring diagram

Not applicable

Connector diagram

Not applicable

Diagnostic Procedure

Step

Inspection

Results

Action

1

VERIFY PCM DTC

•  Using the M-MDS, perform the PCM DTC inspection.
(See DTC INSPECTION.)

•  Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [PCM (SKYACTIV-G (E))].)

(See DTC TABLE [PCM (SKYACTIV-D)].)

(See DTC TABLE [PCM (SKYACTIV-X)].)

DTC troubleshooting completed, then perform the repair completion verification.

No

Go to the next step.

Repair completion verification

VERIFY DTC TROUBLESHOOTING COMPLETED

•  Using the M-MDS, clear the DTC from the EPS control module.
(See CLEARING DTC.)

•  Using the M-MDS, perform the EPS control module DTC inspection.
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

If the CAN communication is normal, perform the diagnosis from Step 1.

•  If the malfunction recurs, replace the PCM.
(See PCM REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].)

(See PCM REMOVAL/INSTALLATION [SKYACTIV-G (WITH CYLINDER DEACTIVATION (E))].)

(See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

(See PCM REMOVAL/INSTALLATION [SKYACTIV-X 2.0].)

No

DTC troubleshooting completed.

System malfunction location		Signal error from PCM
Detection condition		• Error detected in signal from PCM via CAN communication
Fail-safe		• Refer to “Fail-safe Function Table”.(See DTC TABLE [ELECTRIC POWER STEERING (EPS) (E)].)
Possible cause		• PCM malfunction
System wiring diagram		Not applicable
Connector diagram		Not applicable

Step	Inspection	Results	Action
1	VERIFY PCM DTC • Using the M-MDS, perform the PCM DTC inspection. (See DTC INSPECTION.) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [PCM (SKYACTIV-G (E))].) (See DTC TABLE [PCM (SKYACTIV-D)].) (See DTC TABLE [PCM (SKYACTIV-X)].) DTC troubleshooting completed, then perform the repair completion verification.
1		No	Go to the next step.
Repair completion verification	VERIFY DTC TROUBLESHOOTING COMPLETED • Using the M-MDS, clear the DTC from the EPS control module. (See CLEARING DTC.) • Using the M-MDS, perform the EPS control module DTC inspection. (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, perform the diagnosis from Step 1. • If the malfunction recurs, replace the PCM. (See PCM REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].) (See PCM REMOVAL/INSTALLATION [SKYACTIV-G (WITH CYLINDER DEACTIVATION (E))].) (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].) (See PCM REMOVAL/INSTALLATION [SKYACTIV-X 2.0].)
Repair completion verification		No	DTC troubleshooting completed.