Inspection Procedure 3: Abnormality in KOS-ECU power supply and earth circuits.
| caution | Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal. |
PROBABLE CAUSES
- Damaged wiring harness and connectors
- Malfunction of KOS-ECU
DIAGNOSIS PROCEDURE
STEP 1. Connector check: C-10 KOS-ECU connector, C-317 ETACS-ECU connector
Q.
Is the check result normal?


STEP 2. Check the wiring harness between the C-10 KOS-ECU connector terminal No. 7, 8 and the C-417 ETACS-ECU connector terminal No. 5, 10 and between the C-10 KOS-ECU connector terminal No. 4 and the C-01 earth joint connector terminal No. 11.
- Check the power supply line for open and short circuit, and check the earth line for open circuit.
| note | Prior to the wiring harness inspection, check C-04 joint connector (2), C-102 joint connector (3) <RH drive vehicles>, C-108 joint connector (4) intermediate connector and repair if necessary. |
Q.
Is the check result normal?


STEP 3. Retest the system
Q.
Is the check result normal?



