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DTC P0743 [JA5AX-EL]

id050206806500

DTC P0743 | Torque converter clutch (TCC) solenoid valve circuit malfunction (open/short)
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DETECTION CONDITION | • Open or short in TCC solenoid signal system (while TCM monitors solenoid output voltage, the voltage that differs from the ON/OFF signal output by CPU in TCM is detected). Diagnostic support note: • This is continuous monitor (CCM). • MIL illuminates if TCM detects the above malfunction condition during first drive cycle. • PENDING CODE is not available. • FREEZE FRAME DATA is available. • AT warning light does not indication. • DTC is stored in TCM memory.
POSSIBLE CAUSE | • Open circuit between TCC solenoid valve terminal A and TCM terminal 2S • Short to ground between TCC solenoid valve terminal A and TCM terminal 2S • Short to power between TCC solenoid valve terminal A and TCM terminal 2S • TCC solenoid valve malfunction • Damage connector between TCC solenoid valve and TCM • TCM malfunction

## Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY FREEZE FRAME DATA HAS BEEN RECORDED • Has FREEZE FRAME PID DATA been recorded? | Yes | Go to next step.
No | Record FREEZE FRAME PID DATA on repair order, then go to next step.
2 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Check for related Service Bulletins and/or on-line repair information availability. • Is any related repair information available? | Yes | Perform repair or diagnosis according to available repair information. • If vehicle is not repaired, go to next step.
No | Go to next step.
3 | INSPECT TERMINAL COMPONENT NO.1 (12-PIN) FOR POOR CONNECTION • Turn ignition key to OFF. • Disconnect terminal componentNo.1 (12-pin). • Check for poor connection (damaged, pulled-out, terminals, corrosion, etc.). • Are terminals okay? | Yes | Go to next step.
No | Repair or replace terminals, then go to Step 13.
4 | INSPECT RESISTANCE • Check resistance between terminal component No.1 (12-pin) terminal H (transaxle case side) and body ground. • Is resistance within 12-13.2 ohms? (See SOLENOID VALVE INSPECTION [JA5AX-EL].) | Yes | Go to Step 9.
No | Go to next step.
5 | INSPECT COUPLER COMPONENT (10-PIN) FOR POOR CONNECTION • Disconnect coupler component (10-pin) connector. • Check for poor connection (damaged, pulled-out, terminals, corrosion, etc.). • Is terminal okay? | Yes | Go to next step.
No | Repair or replace terminal, then go to Step 13.
6 | INSPECT RESISTANCE • Check resistance between coupler component (10-pin) terminal C (part side) and body ground. • Is resistance within 12-13.2 ohms? (See SOLENOID VALVE INSPECTION [JA5AX-EL].) | Yes | Repair or replace terminal component No.1 (12-pin), then go to Step 13.
No | Go to next step.
7 | INSPECT TCC SOLENOID VALVE CONNECTOR FOR POOR CONNECTION • Disconnect TCC solenoid valve connector. • Check for poor connection (damaged, pulled-out, terminals, corrosion, etc.). • Is terminal okay? | Yes | Go to next step.
No | Repair or replace terminal, then go to Step 13.
8 | INSPECT RESISTANCE • Check resistance between TCC solenoid valve connector (part side) terminal A and body ground. • Is resistance within 12-13.2 ohms? (See SOLENOID VALVE INSPECTION [JA5AX-EL].) | Yes | Repair or replace coupler component (10-pin), then go to Step 13.
No | Verify TCC solenoid valve installation. • If TCC solenoid valve is installed correctly, replace TCC solenoid valve, then go to Step 13. (See SOLENOID VALVE REMOVAL/INSTALLATION [JA5AX-EL].)
9 | INSPECT TCM CONNECTOR FOR POOR CONNECTION • Disconnect TCM connector. • Check for poor connection (damaged, pulled-out, terminals, corrosion, etc.). • Are terminals okay? | Yes | Go to next step.
No | Repair terminals, then go to Step 13.
10 | INSPECT TERMINAL COMPONENT NO.1 (12-PIN) CIRCUIT FOR OPEN CIRCUIT • Check continuity between TCM terminal 2S (harness-side) and terminal component No.1 (12-pin) terminal H (harness-side). • Is there continuity between terminals? | Yes | Go to next step.
No | Repair or replace harness, then go to Step 13.
11 | INSPECT TERMINAL COMPONENT NO.1 (12-PIN) CIRCUIT FOR SHORT TO POWER • Turn ignition key to ON (engine OFF). • Check voltage at terminal component No.1 (12-pin) terminal H (harness-side). • Is voltage 0 V? | Yes | Go to next step.
No | Repair or replace harness, then go to Step 13.
12 | INSPECT TCM CIRCUIT FOR SHORT TO GROUND • Turn ignition key to OFF. • Check continuity between TCM terminal 2S (harness-side) and body ground. • Is there any continuity? | Yes | Repair or replace harness, then go to next step.
No | Go to next step.
13 | VERIFY TROUBLESHOOTING OF DTC P0743 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear DTC from memory using WDS or equivalent. • Drive vehicle in D range and make sure that gears shift smoothly from 1GR to 5GR. • Is same DTC present? | Yes | Replace TCM, then go to next step. (See TCM REMOVAL/INSTALLATION [JA5AX-EL].)
No | Go to next step.
14 | VERIFY AFTER REPAIR PROCEDURE • Perform "After Repair Procedure". (See AFTER REPAIR PROCEDURE [JA5AX-EL].) • Is there any DTC present? | Yes | Go to applicable DTC inspection.
No | Troubleshooting completed.