Diagnosis Item 12: Diagnose when the M.U.T.-III cannot receive the data sent by WCM

caution

When servicing a CAN bus line, earth yourself by touching a metal object such as an unpainted water pipe. If you fail to do, a component connected to the CAN bus line may be broken.

FUNCTION

If the M.U.T.-III can not communicate with the WCM, this diagnosis result will be set.

TRUBLE JUDGEMENT CONDITIONS

If a communication flag is not set for the WCM, the ETACS-ECU determines that there is a failure.

TROUBLESHOOTING HINTS

Malfunction of the connector [joint connector (CAN1) or WCM connector improperly connected]
Malfunction of the wiring harness [open circuit between the WCM connector and the joint connector (CAN1), or power supply circuit to the WCM]
Malfunction of the WCM

DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-105 joint connector (CAN1) and C-33 WCM connector

caution

The strand end of the twist wire should be within 10 cm from the connector. For details refer to

Q. Is the check result normal?

	Go to Step 2.

	Repair the defective connector.

STEP 2. Check the wiring harness between C-33 WCM connector and C-105 joint connector (CAN1)

caution

Strictly observe the specified wiring harness repair procedure. For details refer to

Disconnect WCM connector and joint connector (CAN1), and check the following wiring harness.

The wiring harness between C-33 WCM connector terminal No.11 and C-105 joint connector (CAN1) terminal No.5 <CAN_H>
The wiring harness between C-33 WCM connector terminal No.10 and C-105 joint connector (CAN1) terminal No.16 <CAN_L>

Q. Is the check result normal?

	Check the power supply circuit of the WCM. Refer to Group 42C - WCM - Troubleshooting .

	Repair the wiring harness.