Diagnostic Procedure 21

SYMPTOM:
O/D OFF indicator lamp does not come on in TCM self-diagnostic procedure even the lamp circuit is good.

DESCRIPTION
- Inhibitor switch
Detects the selector lever position and sends a signal to the TCM.
- Overdrive control switch
Detects the overdrive control switch position (ON or OFF) and sends a signal to the TCM.
- Throttle position switch
Consists of a wide open throttle position switch and a closed throttle position switch.
The wide open throttle position switch sends a signal to the TCM when the throttle valve is open at least 1/2 of the full throttle position. The closed throttle position switch sends a signal to the TCM when the throttle valve is fully closed.











DIAGNOSTIC PROCEDURE

COMPONENT INSPECTION
Overdrive Control Switch







- Check continuity between terminals (5) and (6).

Inhibitor Switch











1. Check continuity between terminals (1) and (2) and between terminals (3) and (4), (5), (6), (7), (8), (9) while moving manual shaft through each position.
2. If NG, check again with manual control cable disconnected from manual shaft of Art assembly. Refer to step 1.
3. If OK on step 2, adjust manual control cable.
4. If NG on step 2, remove inhibitor switch from A/T and check continuity of inhibitor switch terminals. Refer to step 1.
5. If OK on step 4, adjust inhibitor switch.
6. If NG on step 4, replace inhibitor switch.


Throttle Position Switch








Closed throttle position switch (idle position)
- Check continuity between terminals (2) and (4).








Wide open throttle position switch
- Check continuity between terminals (1) and (4).