A/T Does Not Perform Lock-Up

SYSTEM SYMPTOM


A/T Does Not Perform Lock-up


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

DIAGNOSTIC PROCEDURE
1.CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to Diagnosis System (TCM).
Do the self-diagnostic results indicate torque converter clutch solenoid valve, engine speed signal, turbine revolution sensor, accelerator pedal position sensor, CAN communication?
YES - Check the malfunctioning system. Refer to P0740, P0725 P0725 P0725 P0725 P0725 P0725, "Diagnosis
Procedure", P0717, P2138, A/T Control System A/T Control System A/T Control System A/T Control System A/T Control System, "Diagnosis
Procedure".
NO - GO TO 2.
2.CHECK A/T FLUID LEVEL





Check A/T fluid level. Refer to Checking The A/T Fluid (ATF), "Checking the A/T Fluid
(ATF)".
OK or NG
OK - GO TO 3.
NG - Refill ATF.
3.CHECK LINE PRESSURE





Check line pressure at the engine stall point. Refer to Line Pressure Test.
OK or NG
OK - GO TO 6.
NG - 1 - Line pressure high. GO TO 4.
NG - 2 - Line pressure low. GO TO 5.
4.DETECT MALFUNCTIONING ITEM
1. Check control valve with TCM. Refer to Service and Repair.
2. Disassemble A/T. Refer to Disassembly.
3. Check the following items:
- Oil pump assembly. Refer to Oil Pump.
OK or NG
OK - GO TO 7.
NG - Repair or replace damaged parts.
5.DETECT MALFUNCTIONING ITEM
1. Check control valve with TCM. Refer to Service and Repair.
2. Disassemble A/T. Refer to Disassembly.
3. Check the following items:
- Oil pump assembly. Refer to Oil Pump.
- Power train system. Refer to Disassembly.
- Transmission case. Refer to Disassembly.
OK or NG
OK - GO TO 7.
NG - Repair or replace damaged parts.
6.CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to Service and Repair.





2. Check A/T fluid condition. Refer to Checking The A/T Fluid (ATF), "Checking the A/T
Fluid (ATF)".
OK or NG
OK - GO TO 7.
NG - GO TO 10.
7.DETECT MALFUNCTIONING ITEM
- Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to Symptom Table (Symptom No.24).
OK or NG
OK - GO TO 8.
NG - Repair or replace damaged parts.
8.CHECK SYMPTOM
Check again. Refer to Cruise Test - Part 1.
OK or NG
OK >> INSPECTION END
NG - GO TO 9.
9.PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to A/T Control System.
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness connector.
OK or NG
OK >> INSPECTION END
NG - Repair or replace damaged parts.
10.DETECT MALFUNCTIONING ITEM
- Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to Symptom Table (Symptom No.24).
OK or NG
OK - GO TO 8.
NG - Repair or replace damaged parts.