For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

DTC P0741: Torque Converter Clutch (TCC) System - Stuck Off
DTC P0742: Torque Converter Clutch (TCC) System - Stuck On

### Circuit/System Description

The transmission control module (TCM) controls the torque converter clutch (TCC) solenoid valve pulse width modulation (PWM). The solenoid directs the hydraulic fluid for TCC apply and release. When the TCC is applied, the engine is coupled directly to the transmission through the TCC. The TCC slip speed should be near 0. When the TCC is released, the engine is coupled by fluid to the transmission and TCC slip speeds of -300 RPM to +1,500 RPM, during heavy acceleration, are normal.

### Conditions for Running the DTC

#### P0741

• | No Throttle DTCs P0120, P1791 or P1795.

• | No ISS DTCs P0716 or P0717.

• | No OSS DTCs P0722 or P0723.

• | No TCC stuck ON DTC P0742.

• | No IMS DTCs P182A, P182C, P182D, P182E, P182F or P1915.

• | No engine torque signal circuit DTC P2637.

• | No TCC solenoid electrical DTCs P2763 or P2764.

• | The engine run time is greater than 5 seconds.

• | The IMS range is D2, D3, D4, or D5.

• | The elapsed time since the most recent range change is 6 seconds.

• | The transmission fluid temperature is 20-130°C (68-266°F).

• | The engine torque is greater than 55 N·m (41 lb ft).

• | The throttle position is 10-90 percent.

• | The gear ratio is within the following ranges:

- | 1.56:1 to 1.64:1 - 3rd gear

- | 0.98:1 to 1.03:1 - 4th gear

- | 0.73:1 to 0.77:1 - 5th gear

• | The TCC pressure is at least 200 kPa (29 psi) for 2 seconds or more.

• | The TCC duty cycle is at least 80 percent for 2 seconds or more.

#### P0742

• | No Throttle DTCs P0120, P1791 or P1795.

• | No ISS DTCs P0716 or P0717.

• | No OSS DTCs P0722 or P0723.

• | No TCC stuck ON DTC P0741.

• | No IMS DTCs P182A, P182C, P182D, P182E, P182F or P1915.

• | No engine torque signal circuit DTC P2637.

• | No TCC solenoid electrical DTCs P2763 or P2764.

• | The engine run time is greater than 5 seconds.

• | The IMS range is D5.

• | The transmission fluid temperature is 20-130°C (68-266°F).

• | The engine torque is greater than 80 N·m (59 lb ft).

• | The throttle position is 12-90 percent.

• | The transmission is not in 1st gear and the gear ratio is 0.73:1 to 2.27:1.

• | The vehicle speed is greater than 15 km/h (9 mph).

### Conditions for Setting the DTC

#### P0741

The TCM commands the TCC ON, and the TCC slip is between 150-250 RPM for greater than 8 seconds, 2 times during the same ignition.

#### P0742

The TCM commands the TCC ON, and the TCC slip is between -20 RPM and 20 RPM for 3.5 seconds, 3 times during the same ignition.

### Action Taken When the DTC Sets

#### P0741

• | DTC P0741 is a Type B DTC.

• | The TCM inhibits 5th gear if the transmission is in Hot Mode.

• | The TCM commands TCC OFF.

• | The TCM freezes transmission adaptive functions.

#### P0742

• | DTC P0742 is a Type B DTC.

• | The TCM inhibits 5th gear if the transmission is in Hot Mode.

• | The TCM freezes transmission adaptive functions.

### Conditions for Clearing the DTC

DTCs P0741 and P0742 are Type B DTCs.

### Diagnostic Aids

If the DTC is cleared, then will not reset when the vehicle is driven, some of the following conditions may exist:

• | Fluid contamination

• | Plugged fluid circuits

• | Restricted fluid circuits

• | Inspect transmission fluid lines to radiator. Lines may be pinched, plugged or twisted.

• | Refer to Shift Solenoid Valve State and Gear Ratio.

### Reference Information

#### Schematic Reference

Automatic Transmission Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Transmission General Description

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Transmission Control Module Scan Tool Information

### Circuit/System Verification

Perform the Transmission Fluid Check to verify correct fluid level and condition. The transmission fluid level should be within the crosshatch band and the transmission fluid should be red or dark brown.

⇒ | If the transmission fluid is low or discolored, refer to Automatic Transmission Fluid and Filter Replacement.

### Circuit/System Testing

Using the scan tool, clear the DTC. If DTC P0741 was set, operate the vehicle in D5 at 72 km/h (45 mph) and use the scan tool to command the TCC ON. Observe the TCC Slip Speed parameter on the scan tool. The TCC Slip Speed should be between -20 to 75 RPM.

⇒ | If the TCC Slip Speed is between 150-250 RPM for greater than 8 seconds, inspect for the following and repair/replace as necessary:

• | The cooling system for plugging--the cooling lines may be pinched. Refer to Transmission Fluid Cooler Flushing and Flow Test.

• | Inspect the front control valve body assembly for the TCC PWM solenoid valve sticking or leaking. Also inspect the TCC regulator apply valve for sticking. Refer to Torque Converter Clutch Solenoid Replacement.

• | Inspect the rear control valve body assembly for the control valve body ball check valve #2 stuck or missing. Refer to Control Valve Body Accumulator Assembly Replacement.

• | Inspect the fluid pump assembly for the TCC control valve stuck in the OFF position. Also inspect the TCC enable valve stuck in the OFF position. Refer to Transmission Fluid Pump Disassemble and Transmission Fluid Pump Assemble.

• | Inspect the forward clutch input housing assembly for the input shaft fluid seal ring leaking or worn. Refer to Forward and Coast Clutch Disassemble.

⇒ | If the TCC Slip Speed is between -20 and 20 RPM for greater than 4 seconds, inspect for the following and repair/replace as necessary:

• | Inspect the TCC PWM solenoid valve sticking or leaking. Also inspect the TCC regulator apply valve for sticking. Refer to Torque Converter Clutch Solenoid Replacement.

• | Clogged exhaust orifice in the TCC solenoid valve.

• | Converter clutch apply valve stuck in the apply position.

• | Misaligned or damaged valve body gasket.

• | Restricted release passage.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• | Automatic Transmission Fluid and Filter Replacement

• | Transmission Fluid Cooler Flushing and Flow Test

• | Torque Converter Clutch Solenoid Replacement

• | Control Valve Body Accumulator Assembly Replacement

• | Transmission Fluid Pump Disassemble

• | Transmission Fluid Pump Assemble

• | Forward and Coast Clutch Disassemble