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DTC P0742 [FN4A-EL]

id0502a1808000

DTC P0742 | Torque converter clutch (TCC) stuck ON
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DETECTION CONDITION | • All of following conditions are satisfied under each of following throttle conditions. - ATF temperature 20 °C {68 °F} or above. - Driving in 4GR at D range. - Engine running. - Turbine speed within 225-4,988 rpm. - Vehicle speed below 70 km/h {43 mph}. - Torque converter clutch (TCC) no operation - Difference between engine speed and turbine speed below 50 rpm - DTC P0734 not output • Throttle conditions. - Throttle opening angle (TP PID) above 10.1% and 5 s or more have passed. - Throttle opening angle (TP PID) within 3.1-10.1% and 3 s or more have passed. - Throttle opening angle at closed throttle position and 5 s or more have passed. Diagnostic support note: • This is a continuous monitor (CCM). • MIL does not illuminate if PCM detects the above malfunction conditions during first drive cycle. • PENDING CODE is not available. • FREEZE FRAME DATA is not available. • HOLD indicator light flashes. • DTC is stored in the PCM memory.
POSSIBLE CAUSE | • ATF level low • Deteriorated ATF • Shift solenoids A, B, C, D, E, and pressure control solenoid stuck • Line pressure low 2-4 brake band slipping 3-4 clutch slipping • Control valve stuck • PCM malfunction

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Check for related Service Bulletins 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.
2 | CHECK ATF CONDITION • Turn the ignition switch off. • Check ATF condition. - Clear red: Normal - Milky: Water mixed in fluid - Reddish brown: Deteriorated ATF • Is it normal? (See Automatic Transaxle Fluid (ATF) Condition Inspection.) | Yes | Go to next step.
No | If ATF color is milky or reddish brown, replace ATF, then go to Step 4. (See AUTOMATIC TRANSAXLE FLUID (ATF) REPLACEMENT [FN4A-EL].)
3 | CHECK ATF LEVEL • Start engine. • Warm up ATX. • Is ATF level within specification? (See Automatic Transaxle Fluid (ATF) Level Inspection.) | Yes | Go to next step.
No | Adjust ATF level, then go to Step 6. (See Automatic Transaxle Fluid (ATF) Level Inspection.)
4 | INSPECT LINE PRESSURE • Start engine. • Measure line pressure. Specification D, S, L range Idle: 330-470 kPa {3.4-4.7 kgf/cm 2, 48-68 psi} Stall: 1,030-1,190 kPa {10.5-12.1 kgf/cm 2, 150-172 psi} R position Idle: 490-710 kPa {5.0-7.2 kgf/cm 2, 71-102 psi} Stall: 1,700-2,050 kPa {17.4-20.9 kgf/cm 2, 247-297 psi} • Is line pressure within specification? (See Line Pressure Test.) | Yes | Go to next step.
No | • All ranges: Replace oil pump or control valve body, then go to Step 6. • Any ranges: Replace ATX, then go to Step 6. (See AUTOMATIC TRANSAXLE REMOVAL/INSTALLATION [FN4A-EL].) (See ATX Workshop Manual FN4A-EL (9999-95-FN4A-99).)
5 | CHECK OPERATION OF EACH VALVE AND EACH SPRING • Turn the ignition switch off. • Remove control valve body. • Disassemble control valve body. • Is each valve operation normal and is return spring normal? (See CONTROL VALVE BODY REMOVAL [FN4A-EL], CONTROL VALVE BODY INSTALLATION [FN4A-EL].) (See ATX Workshop Manual FN4A-EL (9999-95-FN4A-99).) | Yes | Replace ATX, then go to next step. (See AUTOMATIC TRANSAXLE REMOVAL/INSTALLATION [FN4A-EL].) (See ATX Workshop Manual FN4A-EL (9999-95-FN4A-99).)
No | Repair or replace shift valve and return spring, then go to next step. (See CONTROL VALVE BODY REMOVAL [FN4A-EL], CONTROL VALVE BODY INSTALLATION [FN4A-EL].) (See ATX Workshop Manual FN4A-EL (9999-95-FN4A-99).)
6 | VERIFY TROUBLESHOOTING OF DTC P0742 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear DTC from memory using WDS or equivalent. • Start engine. • Warm up engine and ATX. • Drive vehicle under following. - ATF temperature: 20 °C {68 °F} or above - Drive in D range, 4th gear (TCC not in operation) - Vehicle speed: below 70 km/h {43 mph}. • Throttle conditions - Throttle opening angle (TP PID) above 10.1% and 5 s or more have passed. - Throttle opening angle (TP PID) within 3.1-10.1% and 3 s or more have passed. - Throttle opening angle at closed throttle position and 5 s or more have passed. • Are any DTCs present? | Yes | Replace PCM, then go to next step. (See PCM REMOVAL/INSTALLATION.)
No | Go to next step.
7 | VERIFY AFTER REPAIR PROCEDURE • Perform "After Repair Procedure". (See AFTER REPAIR PROCEDURE [FN4A-EL].) • Are any DTCs present? | Yes | Go to applicable DTC inspection.
No | Troubleshooting completed.