TCM Self-Diagnosis Does Not Activate {Park/Neutral Position (PNP), Overdrive Control and Throttle Position Sensor [Accelera
21. TCM Self-diagnosis Does Not Activate {Park/neutral Position (PNP), Overdrive Control and Throttle Position Sensor [Accelerator Pedal Position (APP) Sensor] Switches Circuit Checks}SYMPTOM: O/D OFF indicator lamp does not come on in TCM self-diagnostic procedure even if the lamp circuit is good.
DESCRIPTION
^ Park/neutral position (PNP) switch
The park/neutral (PNP) switch assembly includes a transmission range switch. The transmission range 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 sensor [accelerator pedal position (APP) sensor]
The throttle position sensor [accelerator pedal position (APP) sensor] is part of the system that controls the throttle position. This system also uses an electric throttle control actuator, which consists of a throttle control motor and throttle position sensors. Accelerator pedal position signal is sent to the ECM.
DIAGNOSTIC PROCEDURE
NOTE: The diagnostic procedure includes inspections for the overdrive control switch circuits.
1. CHECK PARK/NEUTRAL POSITION (PNP) SWITCH CIRCUIT (WITH CONSULT-II)
With CONSULT-II
1. Turn ignition switch to ON position. (Do not start engine.)
2. Select TCM INPUT SIGNALS in DATA MONITOR mode for A/T with CONSULT-II.
3. Read out P/N, R, D, 2 and 1 position switches moving selector lever to each position.
Check that the signal of the selector lever position is indicated properly.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2. DETECT MALFUNCTIONING ITEM
Check the following items:
^ Park/neutral position (PNP) switch
^ Check continuity between park/neutral position (PNP) switch F29 terminals 1 (G/OR) and 2 (B) and between terminals 3 (Y) and 4 (OR), 5 (L), 6 (W/G), 7 (BR/W), 8 G/W), 9 (G) while moving manual shaft through each position.
^ If NG, check again with manual control cable disconnected from manual shaft of A/T assembly. Refer to step a.
^ If OK on step b, adjust manual control cable. Refer to Control Cable Adjustment.
^ If NG on step b, remove park/neutral position (PNP) switch from A/T and check continuity of park/neutral position (PNP) switch terminals. Refer to step a.
^ If OK on step d, adjust park/neutral position (PNP) switch. Refer to Park/Neutral Position (PNP) Switch Adjustment.
^ If NG on step d, replace park/neutral position (PNP) switch. Harness for short or open between ignition switch and park/neutral position (PNP) switch (Main harness) Harness for short or open between park/neutral position (PNP) switch and TCM (Main harness)
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
3. CHECK PARK/NEUTRAL POSITION (PNP) SWITCH CIRCUIT (WITHOUT CONSULT-II)
Without CONSULT-II
1. Turn ignition switch to ON position. (Do not start engine.)
2. Check voltage between TCM terminals 26 (OR), 27 (L), 34 (W/G), 35 (G/W), 36 (BR/W) and ground while moving selector lever through each position.
Voltage:
B: Battery voltage
0: 0V
OK or NG
OK >> GO TO 6.
NG >> GO TO 4.
4. DETECT MALFUNCTIONING ITEM
Check the following items:
^ Park/neutral position (PNP) switch
^ Check continuity between park/neutral position (PNP) switch F29 terminals 1 (G/OR) and 2 (B) and between terminals 3 (Y) and 4 (OR), 5 (L), 6 (W/G), 7 (BR/W), 8 G/W), 9 (G) while moving manual shaft through each position.
^ If NG, check again with manual control cable disconnected from manual shaft of A/T assembly. Refer to step a.
^ If OK on step b, adjust manual control cable. Refer to Control Cable Adjustment.
^ If NG on step b, remove park/neutral position (PNP) switch from A/T and check continuity of park/neutral position (PNP) switch terminals. Refer to step a.
^ If OK on step d, adjust park/neutral position (PNP) switch. Refer to Park/Neutral Position (PNP) Switch Adjustment.
^ If NG on step d, replace park/neutral position (PNP) switch. Harness for short or open between ignition switch and park/neutral position (PNP) switch (Main harness) Harness for short or open between park/neutral position (PNP) switch and TCM (Main harness)
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
5. CHECK OVERDRIVE CONTROL SWITCH CIRCUIT (WITH CONSULT-II)
With CONSULT-II
1. Turn ignition switch to ON position. (Do not start engine.)
2. Select TCM INPUT SIGNALS in DATA MONITOR mode for A/T with CONSULT-II.
3. Read out OVERDRIVE SW.
Check the signal of the overdrive control switch indicated properly. (Overdrive control switch ON displayed on CONSULT-II means overdrive OFF.)
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6. DETECT MALFUNCTIONING ITEM
Check the following items:
^ Overdrive control switch M44.
^ Check continuity between terminals 1 and 2.
^ Harness for short or open between TCM and overdrive control switch (Main harness)
^ Harness of ground circuit for overdrive control switch (Main harness) for short or open
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7. CHECK THROTTLE POSITION SENSOR [ACCELERATOR PEDAL POSITION (APP) SENSOR]
^ Perform throttle position sensor [accelerator pedal position (APP) sensor] inspection. Refer to AT-559, DTC P1705 THROTTLE POSITION SENSOR [ACCELERATOR PEDAL POSITION (APP) SENSOR]. P1705
OK or NG
OK >> GO TO 8.
NG >> Repair or replace damaged parts.
8. CHECK TCM INSPECTION
1. Perform TCM input/output inspection. Refer to AT-480, TCM INSPECTION TABLE. Symptom Chart
OK or NG
OK >> INSPECTION END.
NG >> Inspect TCM terminals and related wiring harnesses for damage or loose connections.
Repair or replace damaged parts.