A/T Does Not Perform Lock-Up

12. A/T Does Not Perform Lock-up

SYMPTOM: A/T does not perform lock-up at the specified speed.

1. CHECK SELF-DIAGNOSTIC RESULTS





Does self-diagnosis show damage to A/T fluid temperature sensor, vehicle speed sensor-A/T (revolution sensor), engine speed signal, torque converter clutch solenoid valve, or vehicle speed sensor-MTR circuit after cruise test?
Yes or No
Yes >> Check torque converter clutch solenoid valve circuit.
No >> GO TO 2.

2. CHECK THROTTLE POSITION SENSOR [ACCELERATOR PEDAL POSITION (APP) SENSOR]





Check throttle position sensor [accelerator pedal position (APP) sensor].
OK or NG
OK >> GO TO 3.
NG >> Repair or replace throttle position sensor [accelerator pedal position (APP) sensor].

3. DETECT MALFUNCTIONING ITEM
1. Remove control valve.
2. Check the following items:
- Torque converter clutch control valve
- Torque converter relief valve
- Pilot valve
- Pilot filter
3. Remove A/T.
4. Check torque converter.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.

4. CHECK SYMPTOM
Check again.
OK or NG
OK >> INSPECTION END
NG >>
1. Perform TCM input/output signal inspection.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.