DTC U0423:00

id060200818300

DTC U0423:00

CAN system communication error

DETECTION CONDITION

•  Error detected in signal from instrument cluster via CAN communication

FAIL-SAFE FUNCTION

•  Control enabled

―  If the EPS CM detects the signal that a engine speed is below the specified value, it disables assistance

•  Power steering malfunction indicator light: Not illuminated

―  If the EPS CM detects the signal that a engine speed is below the specified value, it illuminates the power steering malfunction indicator light

POSSIBLE CAUSE

•  EPS CM detects the signal that a engine speed is below the specified value

•  Abnormal engine switch status is detected

•  PCM malfunction

•  Instrument cluster malfunction

SYSTEM WIRING DIAGRAM

—

Diagnostic Procedure

Step

Inspection

Action

1

INSPECT FOR INSTRUMENT CLUSTER MALFUNCTION

•  Using the M-MDS, perform the DTC inspection for the instrument cluster.
(See DTC INSPECTION [INSTRUMENT CLUSTER].)

•  Are any DTCs detected?

Yes

Go to applicable DTC inspection.

(See DTC TABLE [INSTRUMENT CLUSTER].)

DTC troubleshooting completed, then go to the next step.

No

Go to the next step.

2

VERIFY EPS STATUS

•  Start the engine.

•  Turn the steering wheel to the right and left.

•  Is the assist force generated?

Yes

Go to the Step 3.

No

Using the M-MDS, perform the tachometer inspection.

(See INSTRUMENT CLUSTER INSPECTION.)

If the tachometer is abnormal, inspect for the PCM malfunction and the related wiring harnesses.

(See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)

(See ON-BOARD DIAGNOSTIC TEST [MZR 1.6].)

(See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-D 1.5].)

(See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-D 2.2].)

If the PCM and related wiring harnesses are normal, replace the instrument cluster

(See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)

Inspection/replacement completed, then go to the next step.

3

VERIFY THAT THE SAME DTC IS NOT PRESENT

•  Make sure to reconnect all disconnected connectors.

•  Clear the DTC from the memory.
(See ELECTRIC POWER STEERING (EPS) ON-BOARD DIAGNOSIS.)

•  Is the same DTC present?
(See ELECTRIC POWER STEERING (EPS) ON-BOARD DIAGNOSIS.)

Yes

Repeat the inspection from Step 1.

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

(See STEERING WHEEL AND COLUMN REMOVAL/INSTALLATION.)

No

Go to the next step.

5

VERIFY THAT NO OTHER DTCS ARE PRESENT

•  Are any other DTCs output?

Yes

Go to the applicable DTC inspection.

(See ELECTRIC POWER STEERING (EPS) ON-BOARD DIAGNOSIS.)

No

DTC troubleshooting completed.

DTC U0423:00	CAN system communication error
DETECTION CONDITION	• Error detected in signal from instrument cluster via CAN communication
FAIL-SAFE FUNCTION	• Control enabled ― If the EPS CM detects the signal that a engine speed is below the specified value, it disables assistance • Power steering malfunction indicator light: Not illuminated ― If the EPS CM detects the signal that a engine speed is below the specified value, it illuminates the power steering malfunction indicator light
POSSIBLE CAUSE	• EPS CM detects the signal that a engine speed is below the specified value • Abnormal engine switch status is detected • PCM malfunction • Instrument cluster malfunction
SYSTEM WIRING DIAGRAM	—

Step	Inspection		Action
1	INSPECT FOR INSTRUMENT CLUSTER MALFUNCTION • Using the M-MDS, perform the DTC inspection for the instrument cluster. (See DTC INSPECTION [INSTRUMENT CLUSTER].) • Are any DTCs detected?	Yes	Go to applicable DTC inspection. (See DTC TABLE [INSTRUMENT CLUSTER].) DTC troubleshooting completed, then go to the next step.
1		No	Go to the next step.
2	VERIFY EPS STATUS • Start the engine. • Turn the steering wheel to the right and left. • Is the assist force generated?	Yes	Go to the Step 3.
2		No	Using the M-MDS, perform the tachometer inspection. (See INSTRUMENT CLUSTER INSPECTION.) If the tachometer is abnormal, inspect for the PCM malfunction and the related wiring harnesses. (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See ON-BOARD DIAGNOSTIC TEST [MZR 1.6].) (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-D 1.5].) (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-D 2.2].) If the PCM and related wiring harnesses are normal, replace the instrument cluster (See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.) Inspection/replacement completed, then go to the next step.
3	VERIFY THAT THE SAME DTC IS NOT PRESENT • Make sure to reconnect all disconnected connectors. • Clear the DTC from the memory. (See ELECTRIC POWER STEERING (EPS) ON-BOARD DIAGNOSIS.) • Is the same DTC present? (See ELECTRIC POWER STEERING (EPS) ON-BOARD DIAGNOSIS.)	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the EPS CM, then go to the next step. (See STEERING WHEEL AND COLUMN REMOVAL/INSTALLATION.)
3		No	Go to the next step.
5	VERIFY THAT NO OTHER DTCS ARE PRESENT • Are any other DTCs output?	Yes	Go to the applicable DTC inspection. (See ELECTRIC POWER STEERING (EPS) ON-BOARD DIAGNOSIS.)
5		No	DTC troubleshooting completed.