A/T Does Not Shift D3 To D4

TROUBLE DIAGNOSIS FOR SYMPTOMS


A/T Does Not Shift: D3 to D4


SYMPTOM:
- The vehicle does not shift-up from the D3 to D4 gear at the specified speed.
- The vehicle does not shift-up from the D3 to D4 gear unless A/T is warmed up.

DIAGNOSTIC PROCEDURE
1.CONFIRM THE SYMPTOM
Check if vehicle creeps forward in "D" or "L" position and vehicle can be started from D1
OK or NG
OK - GO TO 2.
NG - Refer to Vehicle Does Not Creep Forward In "D" Or "L" Position, Vehicle Cannot Be Started From D1.
2.CHECK A/T FLUID LEVEL
Check the A/T fluid level. Refer to Inspections Before Trouble Diagnosis.
OK or NG
OK - GO TO 3.
NG - Refill ATF.
3.CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis.
Is any malfunction detected by self-diagnostic?
YES - Check the malfunctioning system.
NO - GO TO 4.
4.DETECT MALFUNCTIONING ITEM
1. Control valve assembly. Refer to Service and Repair.
2. Disassemble A/T. Refer to Disassembly.
3. Check the following items:
- U/D brake. Refer to Disassembly.
- U/D clutch. Refer to Disassembly.
OK or NG
OK - GO TO 6.
NG - Repair or replace damaged parts.
5.CHECK TCM
1. Check TCM input/output signal. Refer to Pinout Values and Diagnostic Parameters.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.
OK or NG
OK - GO TO 5.
NG - Repair or replace damaged parts.
6.CHECK SYMPTOM
Check again.
OK or NG
OK - INSPECTION END
NG - Repair or replace damaged parts.