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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2006 🢒 Optra - Mexico 🢒 Restraints 🢒 SIR 🢒 DTC P0742

DTC P0742 Non European Emissions

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0742 Torque Converter Clutch (TCC) System - Stuck On

Conditions for Setting the DTC
    • Lockup solenoid is stuck ON
    • Drive (D) range is selected
    • Engine water is normal temperature
    • 20 seconds have passed since the transaxle was placed in Drive (D)
    • Engine revolution is 600 RPM or greater
    • No failure of input speed sensor, engine revolution, water temperature signal, solenoid electrical, ranger sensor, throttle signal

Action Taken When the DTC Sets

The transmission control module (TCM) will request the illumination of the hold lamp and store the DTC when the TCM detects failures on 2 consecutive ignition cycles.

Conditions for Clearing the DTC
    • The TCM turns off the hold lamp when no further failures are detected on the next ignition cycles.
    • The scan tool can clear the DTC from the TCM history.
    • The TCM clears the DTC from the TCM history memory after 40 consecutive ignition cycles without fault.

Cause of Failure
    • Lockup solenoid
    •  Inside automatic transmission (A/T)
    • Inside valve body
    • TCM

Step

Action

Yes

No

1
  1. Turn OFF the ignition.
  2. Install the scan tool.
  3. Turn ON the ignition, with the engine OFF.
  4. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu.
  5. Store Freeze Frame/Failure Records.
  6. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu.
  7. Clear DTC Information.
  8. Perform 2 vehicle drive cycles.

Is the hold lamp ON?

Go to Step 2

Go to Step 6

2
  1. Select Request DTC by Status from the Diagnostic Trouble Codes Information menu.
  2. Request DTC by Status.

Is DTC P0742 displayed?

Go to Step 3

Go to Step 6

3
  1. Turn OFF the ignition.
  2. Replace the master transmission control module (TCM) and perform simulation test again under user condition.

Is DTC P0742 displayed?

Go to Step 4

Go to Step 7

4
  1. Estimate the failure of lockup solenoid, lockup clutch or internal valve body.
  2. Inspect the lockup solenoid. Refer to 1, 2 Shift Solenoid, Timing Solenoid, and Lock-Up Solenoid Inspection .

Is the condition of lockup solenoid OK?

Go to Step 5

Go to Step 8

5

Estimate the failure of lockup clutch or internal valve body.

Is a problem found?

Go to Step 9

System OK

6

Repair the temporary connection failure of the connector. Refer to Wiring Harness and Connector Inspection Diagnosis .

System OK

--

7

Replace the TCM. Refer to Transmission Control Module Replacement .

Did you complete the replacement?

System OK

--

8

Replace the lock-up solenoid. Refer to 1, 2 Shift Solenoid, Timing Solenoid, and Lock-Up Solenoid Inspection .

Did you complete the replacement?

System OK

--

9

Replace the valve body assembly. Refer to Control Valve Body Disassemble .

Did you complete the replacement?

System OK

--

DTC P0742 European Emissions

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0742 Torque Converter Clutch (TCC) System - Stuck On

Conditions for Setting the DTC
    • Lockup solenoid is stuck ON
    • Drive (D) range is selected
    • Engine water is normal temperature
    • 20 seconds have passed since the transaxle was placed in Drive (D)
    • Engine revolution is 600 RPM or greater
    • No failure of input speed sensor, engine revolution, water temperature signal, solenoid electrical, ranger sensor, throttle signal

Action Taken When the DTC Sets

The transmission control module (TCM) will request the illumination of the malfunction indicator lamp (MIL) and store the DTC when the TCM detects failures on 2 consecutive ignition cycles.

Conditions for Clearing the DTC
    • The TCM turns off the MIL when no further failures are detected on the next ignition cycles.
    • The scan tool can clear the DTC from the TCM history.
    • The TCM clears the DTC from the TCM history memory after 40 consecutive ignition cycles without fault.

Cause of Failure
    • Lockup solenoid
    •  Inside automatic transmission (A/T)
    • Inside valve body
    • TCM

Step

Action

Yes

No

1
  1. Turn OFF the ignition.
  2. Install the scan tool.
  3. Turn ON the ignition, with the engine OFF.
  4. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu.
  5. Store Freeze Frame/Failure Records.
  6. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu.
  7. Clear DTC Information.
  8. Perform 2 vehicle drive cycles.

Is the malfunction indicator lamp (MIL) ON?

Go to Step 2

Go to Step 6

2
  1. Select Request DTC by Status from the Diagnostic Trouble Codes Information menu.
  2. Request DTC by Status.

Is DTC P0742 displayed?

Go to Step 3

Go to Step 6

3
  1. Turn OFF the ignition.
  2. Replace the master transmission control module (TCM) and perform simulation test again under user condition.

Is DTC P0742 displayed?

Go to Step 4

Go to Step 7

4
  1. Estimate the failure of lockup solenoid, lockup clutch or internal valve body.
  2. Inspect the lockup solenoid. Refer to 1, 2 Shift Solenoid, Timing Solenoid, and Lock-Up Solenoid Inspection .

Is the condition of lockup solenoid OK?

Go to Step 5

Go to Step 8

5

Estimate the failure of lockup clutch or internal valve body.

Is a problem found?

Go to Step 9

System OK

6

Repair the temporary connection failure of the connector. Refer to Wiring Harness and Connector Inspection Diagnosis .

System OK

--

7

Replace the TCM. Refer to Transmission Control Module Replacement .

Did you complete the replacement?

System OK

--

8

Replace the lock-up solenoid. Refer to 1, 2 Shift Solenoid, Timing Solenoid, and Lock-Up Solenoid Inspection .

Did you complete the replacement?

System OK

--

9

Replace the valve body assembly. Refer to Control Valve Body Disassemble .

Did you complete the replacement?

System OK

--