TCM Self-Diagnosis Does Not Activate

TCM Self-diagnosis Does Not Activate

SYMPTOM: A/T CHECK 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.
^ Stop lamp switch signal
Detects the brake pedal state (stop lamp switch is ON or OFF) and sends a signal via CAN communication line to the TCM.
^ Closed throttle position signal
ECM judges throttle opening based on a signal from accelerator pedal position sensor, and sends the signal via CAN communication line to TCM.

DIAGNOSTIC PROCEDURE
1. CHECK PARK/ NEUTRAL POSITION (PNP) SWITCH CIRCUIT
Check the park/neutral position (PNP) switch circuit. Refer to "DTC P0705 PARK/NEUTRAL POSITION SWITCH" P0705.
OK or NG
OK >>GO TO 2.
NG >>Repair or replace damaged parts.

2. CHECK STOP LAMP SWITCH CIRCUIT
Perform self-diagnosis for ABS actuator and electric unit (control unit). Refer to "TROUBLE DIAGNOSIS" (with ABS), "TROUBLE DIAGNOSIS" (with TCS/ABS) or "TROUBLE DIAGNOSIS" (with VDC/TCS/ABS).
OK or NG
OK >>GO TO 3.
NG >>Repair or replace damaged parts.

3. CHECK CLOSED THROTTLE POSITION SIGNAL CIRCUIT
Perform self-diagnosis for ECM. Refer to EC-50, "Emission-related Diagnostic Information".
OK or NG
OK >>GO TO 4.
NG >>Repair or replace damaged parts.

4. CHECK DATA MONITOR (WITH CONSULT-II)
With CONSULT-II
1. Turn ignition switch "ON". (Do not start engine.)
2. Select "A/T" with "DATA MONITOR" mode in CONSULT-II.
3. Depress or release accelerator pedal and read out ON/OFF signaling action of the "CLSD THL POS".





4. Depress or release brake pedal and read out ON/OFF signaling action of the "BRAKE SW".
OK or NG
OK >>GO TO 7.
NG >>GO TO 5.

5. CHECK TCM
1. Check TCM input/output signal. Refer to "TCM Input/Output Signal Reference Values". 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 0.
NG >>Repair or replace damaged parts.

6. CHECK CAN COMMUNICATION LINE
Check the CAN communication line. Refer to "DTC U1000 CAN COMMUNICATION LINE" U1000.
OK or NG
OK >>GO TO 7.
NG >>Repair or replace damaged parts.

7. CHECK SYMPTOM
Check again. OK or NG
OK >> INSPECTION END
NG >>Replace the TCM.