Diagnosis Item 15: Diagnose when the M.U.T.-III cannot receive the data sent by SRS-ECU



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 SRS-ECU, this diagnosis result will be set.

TRUBLE JUDGEMENT CONDITIONS


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

TROUBLESHOOTING HINTS




DIAGNOSIS PROCEDURE


STEP 1. Connector check: C-105 joint connector (CAN1) and C-32 SRS-ECU 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-32 SRS-ECU connector and C-105 joint connector (CAN1)


caution Strictly observe the specified wiring harness repair procedure. For details refer to .
Disconnect SRS-ECU connector and joint connector (CAN1), and check the following wiring harness.

  • The wiring harness between C-32 SRS-ECU connector terminal No.10 and C-105 joint connector (CAN1) terminal No.1 <LHD - CAN_H>
  • The wiring harness between C-32 SRS-ECU connector terminal No.10 and C-105 joint connector (CAN1) terminal No.7 <RHD - CAN_H>
  • The wiring harness between C-32 SRS-ECU connector terminal No.9 and C-105 joint connector (CAN1) terminal No.12 <LHD - CAN_L>
  • The wiring harness between C-32 SRS-ECU connector terminal No.9 and C-105 joint connector (CAN1) terminal No.20 <RHD - CAN_L>

Q. Is the check result normal?

Check the power supply circuit of the SRS-ECU. Refer to Group 52B - Troubleshooting .
Repair the wiring harness.