A/T Does Not Shift: D5 -> D4

A/T Does Not Shift: 5th Gear -> 4th Gear

SYMPTOM: When shifted from M5 to M4 position in manual mode, does not downshift from 5th to 4th gear.

DIAGNOSTIC PROCEDURE

1. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT-92, "SELF-DIAGNOSTIC RESULT MODE", AT-102, "TCM SELF-DIAGNOSTIC PROCEDURE (NO TOOLS)".
Self-Diagnostic Result Mode
TCM Self-Diagnostic Procedure (No Tools)
Is any malfunction detected by self-diagnostic results?
YES >> Check the malfunctioning system. Refer to AT-92, "SELF-DIAGNOSTIC RESULT MODE", AT-103, "Judgement Self-diagnosis Code".
Self-Diagnostic Result Mode
TCM Self-Diagnostic Procedure (No Tools)
NO >> GO TO 2.

2. CHECK A/T FLUID LEVEL





Check A/T fluid level.
OK or NG
OK >> GO TO 3.
NG >> Refill [1][2]ATF.

3. CHECK A/T POSITION





Check the A/T position. Refer to AT-231, "Checking of A/T Position". Testing and Inspection
OK or NG
OK >> GO TO 4.
NG >> Adjust A/T position.

4. CHECK MANUAL MODE SWITCH
Check the manual mode switch. Refer to AT-166, "DTC P1815 MANUAL MODE SWITCH". P1815
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.

5. CHECK A/T FLUID CONDITION
1. Remove oil pan.





2. Check A/T fluid condition. Refer to AT-53, "A/T Fluid Condition Check". A/T Fluid Condition Check
OK or NG
OK >> GO TO 6.
NG >> GO TO 9.

6. DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-64, "Symptom Chart" (Symptom No.47). Symptom Chart
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.

7. CHECK SYMPTOM
Check again. Refer to AT-61, "Cruise Test - Part 3". Cruise Test - Part 3
OK or NG
OK >> INSPECTION END
NG >> GO TO 8.

8. CHECK TCM
1. Check TCM input/output signals. Refer to AT-89, "TCM Input/Output Signal Reference Values". Pinout Values and Diagnostic Parameters
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.

9. DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-64, "Symptom Chart" (Symptom No.47). Symptom Chart
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.