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DTC P0742 [FN4A-EL]

BME050201030217

DTC P0742 | Torque converter clutch (TCC) stuck ON
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DETECTION CONDITION | • If all of the following conditions are satisfied under each of the following throttle conditions, the PCM determines that there is a malfunction.

  - ATF temperature 20 °C {68 °F} or more
  - 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) is above 10.1% and 5 s or more have passed.
  - Throttle opening angle (TP PID) is within 3.1-10.1% and 3 s or more have passed.
  - Throttle opening angle is at closed throttle position and 5 s or more have passed.

Diagnostic support note:
• This is a continuous monitor (CCM).
• The MIL does not illuminate if the PCM detects the above malfunction conditions during the first drive cycle.
• A PENDING CODE is not available.
• FREEZE FRAME DATA is not available.
• The HOLD indicator light flashes.
• The DTC is stored in the PCM memory.
POSSIBLE CAUSE | • Low ATF level • Deteriorated ATF • Stuck shift solenoids A, B, C, D, E, and pressure control solenoid • Low line pressure 2-4 brake band slipping
3-4 clutch slipping
• Stuck control valve
• PCM malfunction

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related Service Bulletins and or/on-line repair information availability. • Is any related repair information available? | Yes | Perform repair or diagnosis according to the available repair information. • If the vehicle is not repaired, go to the next step.
No | Go to the next step.
2 | INSPECT ATF CONDITION • Turn the ignition switch to the LOCK position. • Inspect the 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 the next step.
No | If the ATF color is milky or reddish brown, replace the ATF, then go to Step 4. (See AUTOMATIC TRANSAXLE FLUID (ATF) REPLACEMENT [FN4A-EL].)
3 | INSPECT ATF LEVEL • Start the engine. • Warm up the ATX. • Is the ATF level within the specification? (See Automatic Transaxle Fluid (ATF) Level Inspection.) | Yes | Go to the next step.
No | Add the ATF to the specified level, then go to Step 6. (See Automatic Transaxle Fluid (ATF) Level Inspection.)
4 | INSPECT LINE PRESSURE • Start the engine. • Measure the line pressure. Specification Idle: 330-470 kPa {3.4-4.7 kgf/cm 2, 49-66 psi}

Stall: 1,160-1,320 kPa {11.9-13.4 kgf/cm 2, 170-190 psi}

• Are the line pressure within the specifications?
(See Line Pressure Test.)
Yes
Go to the next step.
No | • All ranges: Replace the oil pump or control valve body, then go to Step 6. • Any ranges: Replace the ATX, then go to Step 6. (See AUTOMATIC TRANSAXLE REMOVAL/INSTALLATION [FN4A-EL].) (See ATX Workshop Manual FN4A-EL.)
5 | INSPECT OPERATION OF EACH VALVE AND EACH SPRING • Turn the ignition switch to the LOCK position. • Remove the control valve body. • Disassemble the control valve body. • Is each valve operation and the normal the return spring?
(See CONTROL VALVE BODY REMOVAL [FN4A-EL].)
(See CONTROL VALVE BODY INSTALLATION [FN4A-EL].)
(See ATX Workshop Manual FN4A-EL.)
Yes
Replace the ATX, then go to the next step.
(See AUTOMATIC TRANSAXLE REMOVAL/INSTALLATION [FN4A-EL].)
(See ATX Workshop Manual FN4A-EL.)
No | Repair or replace the shift valve and return spring, then go to the next step. (See CONTROL VALVE BODY REMOVAL [FN4A-EL].) (See CONTROL VALVE BODY INSTALLATION [FN4A-EL].) (See ATX Workshop Manual FN4A-EL.)
6 | VERIFY TROUBLESHOOTING OF DTC P0742 COMPLETED • Make sure to reconnect all the disconnected connectors. • Clear the DTC from the memory using the WDS or equivalent. • Start the engine. • Warm up engine and ATX.
• Drive the vehicle under the following condition.

  - ATF temperature: 20 °C {68 °F} or more
  - Drive in the D range, 4GR (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 the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [L3].)
No | Go to the next step.
7 | VERIFY AFTER REPAIR PROCEDURE • Perform the "After Repair Procedure". (See AFTER REPAIR PROCEDURE [FN4A-EL].) • Are any DTCs present? | Yes | Go to the applicable DTC inspection. (See DTC TABLE [FN4A-EL].)
No | DTC troubleshooting completed.