DTC

U0401:00

CAN communication: signal error from PCM

U0401:86

DETECTION CONDITION

• DTC U0401:00

• Vacuum sensor 2 signal from the PCM is invalid or not within range for a continuous 1 s.

• DTC U0401:86

• Engine speed signal error from the PCM continues for 5 s.

FAIL-SAFE FUNCTION

• Refer to “Fail-safe function table”. (See DTC TABLE [EVP CONTROL UNIT].)

POSSIBLE CAUSE

• PCM malfunction

SYSTEM WIRING DIAGRAM

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Step

Inspection

Action

1

• Using the M-MDS, perform the PCM DTC inspection.

  (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)].)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [PCM (SKYACTIV-G 2.0)].)

DTC troubleshooting completed, then go to the next step.

No

Go to the next step.

2

• Using the M-MDS, clear the DTC from the EVP control unit.

  (See CLEARING DTC [EVP CONTROL UNIT].)

• Using the M-MDS, perform the EVP control unit DTC inspection.

  (See DTC INSPECTION [EVP CONTROL UNIT].)

• Is the same DTC present?

Yes

Repeat the inspection from Step1.

If the malfunction recurs, replace the PCM, then go to the next step.

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

No

Go to the next step.

3

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [EVP CONTROL UNIT].)

No

DTC troubleshooting completed.