Inspection Procedure 40: Oil temperature warning lamp flashes or does not go out


caution Whenever the ECU is replaced, ensure that the CAN bus lines are normal.

COMMENTS ON TROUBLE SYMPTOM


If the oil temperature warning lamp flashes or does not go out, the cause is probably a malfunction of the A/T fluid temperature sensor 2 system or A/T-ECU.
note As the cause for oil temperature warning lamp to flash or not to go out, a combination meter malfunction and combination meter circuit malfunction are suspected. However, it shall be presupposed that no malfunction is present to the combination meter system.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Check of fluid level check mode
Turn the ignition switch from OFF to ON, and check again if the A/T fluid temperature warning lamp illuminates or flashes.
note When the mode is in the fluid check mode (fluid level check mode of A/T Fluid Check <M.U.T.-III not used>), the A/T fluid temperature warning lamp illuminates or flashes. To cancel this status, turn the ignition switch from OFF to ON.

Q. Does the A/T fluid temperature warning lamp illuminate or flash?
Go to Step 2.
This diagnosis is complete.

STEP 2. M.U.T.-III CAN bus diagnostics
Using M.U.T.-III, perform CAN bus line diagnosis.

Q. Is the check result normal?
Go to Step 3.
Repair the CAN bus line (Refer to GROUP 54C - Troubleshooting ), and then go to Step 4.

STEP 3. M.U.T.-III data list
Item 7: A/T fluid temperature sensor 2 (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 4.
Repair the A/T fluid temperature sensor 2 system.

STEP 4. Retest the system

Q. Is the trouble symptom reproduced?
Replace the A/T-ECU.
This diagnosis is complete.