Automatic transmission fluid temperature warning light always on (AWR6B45)

1. Transmission control system check

Refer to "55.Transmission Control 5A.Troubleshooting(AWR6B45) diagnostic system check-transmission controls".

2. Automatic transmission fluid temperature warning light OFF check

1) Turn ON the ignition switch.

2) Check the automatic transmission fluid temperature warning light. Does the automatic transmission fluid temperature warning light illuminate for 3 seconds and then turn OFF?

Yes

Go to Intermittent conditions of automatic transmission.

Refer to "206.Transmission, Transaxle 19D.Symptom(AWR6B45) Intermittent conditions of automatic transmission".

No

=>Go to Automatic transmission fluid temperature warning light illumination check.

3. Automatic transmission fluid temperature warning light illumination check

1) Turn OFF the ignition switch.

2) Disconnect the transmission internal harness connector (E42).

Refer to "LHD Automatic Transmission" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Automatic Transmission" in the ETM (wiring diagram). (Open using the ETM viewer.).

3) Turn ON the ignition switch.

4) Check the automatic transmission fluid temperature warning light. Does the automatic transmission fluid temperature warning light illuminate for 3 seconds and then turn OFF?

Yes

=>Go to ATF cooling system inspection.

No

=>Go to Inspection for short to ground in transmission fluid temperature sensor 1 signal circuit.

4. ATF cooling system inspection

1) Inspect the ATF cooling system for the following. Is the result normal?

Yes

=>Go to Inspection of transmission internal harness.

No

Repair as necessary.

=>Go to Repair verification.

5. Inspection of transmission internal harness

1) Inspect the signal circuit between the transmission internal harness (pin 3 of E42) and transmission fluid temperature sensor 1 for a short to ground or a short to the low reference circuit. Is the result normal?

Refer to "LHD Automatic Transmission" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Automatic Transmission" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

Replace the transmission internal harness.

Refer to "5.Transmission, Transaxle 5B.Automatic(AWR6B45) transmission disassembly".

Refer to "5.Transmission, Transaxle 5B.Automatic(AWR6B45) transmission reassembly".

=>Go to Repair verification.

No

Repair the circuit as necessary.

=>Go to Repair verification.

6. Inspection for short to ground in transmission fluid temperature sensor 1 signal circuit

1) Inspect the transmission fluid temperature sensor 1 signal circuit between the TCM (pin 23 of E5) and the transmission internal harness (pin 3 of E42) for a short to ground or a short to the low reference circuit. Is the result normal?

Refer to "LHD Automatic Transmission" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Automatic Transmission" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to TCM replacement.

No

Repair the circuit as necessary.

=>Go to Repair verification.

7. TCM replacement

Refer to "5.Transmission, Transaxle 5Z.Transmission Electrical Control(AWR6B45) TCM removal".

Refer to "5.Transmission, Transaxle 5Z.Transmission Electrical Control(AWR6B45) TCM installation".

Refer to "5.Transmission, Transaxle 5Z.Transmission Electrical Control(AWR6B45) TCM setting".

Procedure completion

=>Go to Repair verification.

8. Repair verification

1) Reconnect all of the disconnected harness connectors.

2) Turn ON the ignition switch.

3) Check the automatic transmission fluid temperature warning light. Does the automatic transmission fluid temperature warning light illuminate for 3 seconds and then turn OFF?

Yes

The system is normal.

No

=>Go to Automatic transmission fluid temperature warning light illumination check.