Inspection Procedure 2: Vehicle power does not turn ON. (not possible with both of power supply mode ACC and ON)
| caution | Before replacing the ECU,
ensure that the power supply circuit, the earth circuit and the communication circuit are normal. |
COMMENTS ON TROUBLE SYMPTOM
| note | OSS-ECU can communicate with the M.U.T.-III even when the engine switch is in the "OFF" position. |
PROBABLE CAUSES
- Malfunction of battery
- Damaged wiring harness and connectors
- Malfunction of engine switch (poor connector contact, poor engine switch contact)
- Malfunction of the CAN bus line
- Malfunction of OSS-ECU
- ETACS-ECU malfunction
DIAGNOSIS PROCEDURE
STEP 1. Battery check
Q.
Is the check result normal?
STEP 2. Check that the M.U.T.-III communicates with this system.
| note | If ETACS-ECU is not active, OSS-ECU cannot communicate with the M.U.T.-III. |
| (1)Perform the ON/OFF operation of any of the door switches for several times,
or open any of the doors. |
| (2)Check that OSS-ECU can communicate with the M.U.T.-III. |
Q.
Is the check result normal?
STEP 3. M.U.T.-III CAN bus diagnostics
Q.
Is the check result normal?
STEP 4. M.U.T.-III diagnosis code
Q.
Is the diagnosis code set?
STEP 5. Engine switch check
Q.
Is the check result normal?
STEP 6. Check of the troubles
Q.
Is the check result normal?
STEP 7. Check of the troubles
Q.
Is the check result normal?