P0743
DTC P0743 TORQUE CONVERTER CLUTCH CIRCUIT - ELECTRICALCOMPONENT LOCATION:
GENERAL DESCRIPTION
Refer to DTC P0741. P0741
DTC DESCRIPTION
The PCM checks the torque converter clutch control signal by monitoring the feedback signal from the solenoid valve drive circuit. If an unexpected signal is monitored (for example, high voltage is detected when low voltage is expected, or low voltage is detected when high voltage is expected), the PCM judges that the torque converter clutch solenoid valve circuit is malfunctioning and sets this code.
DTC DETECTING CONDITION
DTC DETECTING CONDITION:
SPECIFICATION
Solenoid Valve for Pressure Control
- Sensor type: Normal open 3-way
- Operating temperature: -22 - 266°F (-30 - 130°C)
- Frequency:
- LR, 2ND, UD, OD, RED: 61.27 Hz (at the ATF temp. -20°C above)
- DCC 30.64 Hz
- VFS 600 ± 20 Hz
- Internal resistance:
- 2.6-3.49 (68°F or 20°C) - LR, 2ND, UD, OD, RED, DCC
- 4.0 - 4.7 Ohms (68°F or 20°C) - VFS
- Surge voltage: 56 V (except VFS)
MONITOR SCAN TOOL DATA
1. Connect SCAN TOOL to data link connector (DLC)
2. Engine ON.
3. Monitor the TCC SOL. VALVE parameter on the SCAN TOOL
4. Select D RANGE and Operate TCC SOLENOID DUTY more than 85%
5. Does TCC SOLENOID DUTY follow the reference data?
YES > Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration or damage. Repair or replace as necessary and go to Verification of Vehicle Repair procedure.
NO > Go to Terminal & connector inspection procedure.
TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES > Repair as necessary and then go to verification of vehicle repair procedure.
NO > Go to Power supply circuit inspection procedure.
POWER SUPPLY CIRCUIT INSPECTION
1. Disconnect A/T SOLENOID VALVE connector.
2. Measure voltage between terminal 6 of the sensor harness connector and chassis ground.
3. Turn ignition switch OFF - ON
Specification: 12V is measured only for approximately 0.5 sec
Specification:
4. Is voltage within specifications?
YES > Go to Signal circuit inspection procedure.
NO > Check that A/T-20A fuse in engine room junction is installed or not blown. Check for open in harness. Repair as necessary and go to Verification of Vehicle Repair procedure.
SIGNAL CIRCUIT INSPECTION
1. Check signal circuit open inspection.
1. Ignition OFF.
2. Disconnect A/T SOLENOID VALVE connector and PCM connector.
3. Measure resistance between terminal 9 of the ATM SOLENOID VALVE harness connector and terminal 43 of the PCM harness connector B.
Specification: approximately 0 Ohms
Specification:
4. Is resistance within specifications?
YES > Go to Check signal circuit short inspection procedure.
NO > Check for open in harness. Repair as necessary and go to Verification of Vehicle Repair procedure.
2. Check signal circuit short inspection
1. Ignition OFF.
2. Disconnect A/T SOLENOID VALVE connector and PCM connector.
3. Measure resistance between terminal 9 of the ATM SOLENOID VALVE harness and chassis ground.
Specification: Infinite
Specification:
4. Is resistance within specifications?
YES > Go to Component inspection procedure.
NO > Check for short to ground in harness. Repair as necessary and go to Verification of Vehicle Repair procedure.
COMPONENT INSPECTION
1. CHECK SOLENOID VALVE
1. Ignition OFF.
2. Disconnect A/T SOLENOID VALVE connector.
3. Measure resistance between terminal 9 and terminal 6 of the ATM SOLENOID VALVE harness connector.
Specification: Approximately 2.6 - 3.4 Ohms [20°C (68°F)]
Specification:
4. Is resistance within specification?
YES > Go to CHECK PCM.
NO > Replace TCC SOLENOID VALVE as necessary and go to Verification of Vehicle Repair procedure.
2. CHECK PCM
1. Connect SCAN TOOL to data link connector (DLC).
2. Ignition ON & Engine OFF.
3. Select A/T solenoid valve actuator test and operate actuator test.
4. Can you hear operating sound for TCC SOLENOID VALVE actuator testing function?
YES > Go to Verification of Vehicle Repair procedure.
NO > Replace PCM as necessary and go to Verification of Vehicle Repair procedure.
ACTUATOR TEST CONDITION
1. IG SWITCH ON
2. TRANSAXLE RANGE SWITCH is normal
3. P RANGE
4. Vehicle Speed 0 km/h
5. Throttle position sensor < 1 V
6. IDLE SWITCH ON
7. ENGINE RPM 0
VERIFICATION OF VEHICLE REPAIR
Refer to DTC P0741. P0741