For 1990-2009 cars
Automatic Transmission Components
Automatic Transmission Controls Schematics
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

### Circuit Description

The PCM controls the torque converter clutch pulse width modulation (TCC PWM) solenoid valve. The solenoid controls the hydraulic fluid for TCC apply and release. When the TCC is fully applied, the engine is coupled directly to the transmission through the TCC.

The TCC used is an electronically controlled capacity clutch (ECCC). The PCM will normally allow a small amount of slip to occur with the ECCC. When the TCC is engaged, TCC slip speed is maintained at approximately 20 to 50 RPM.

If the PCM detects high torque converter slip when the TCC is commanded ON, then DTC P0741 sets. DTC P0741 is a type B DTC.

### Conditions for Running the DTC

• | No TP sensor DTC P0121, P0122 or P0123.

• | No VSS DTC P0502 or P0503.

• | No AT ISS sensor DTC P0716 or P0717.

• | No TCC stuck ON DTC P0742.

• | No TFP manual valve position switch DTC P1810.

• | No TCC PWM solenoid valve DTC P1860.

• | No TCC release switch DTC P1887.

• | The engine speed is greater than 500 RPM for 5 seconds and not in fuel shut off.

• | The transmission gear range is D4, D3 or D2.

• | The time since the last gear range change is greater than 6 seconds.

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

• | The TP angle is 4-35%.

• | The TCC PWM solenoid valve is commanded ON for more than 0.5 seconds.

• | The TCC is at maximum apply pressure.

### Conditions for Setting the DTC

The TCC slip speed is greater than 180 RPM two times for 7 seconds each, during the same ignition cycle.

### Action Taken When the DTC Sets

• | The PCM illuminates the malfunction indicator lamp (MIL) during the second consecutive trip in which the conditions for setting the DTC are met.

• | The PCM inhibits TCC.

• | The PCM inhibits 4th gear if the transmission is in Hot Mode.

• | The PCM freezes shift adapts.

• | The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Freeze Frame and Failure Records.

• | The PCM stores DTC P0741 in PCM history during the second consecutive trip in which the conditions for setting the DTC are met.

### Conditions for Clearing the MIL/DTC

• | The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.

• | A scan tool can clear the MIL/DTC.

• | The PCM clears the DTC from the PCM history if the vehicle completes 40 consecutive warm-up cycles without an emission-related diagnostic fault occurring.

• | The PCM cancels the DTC default actions when the fault no longer exists and the ignition switch is OFF long enough in order to power down the PCM.

### Diagnostic Aids

• | Inspect the connectors at the controller, the component and all other circuit connecting points for an intermittent condition. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

• | Inspect the circuit wiring for an intermittent condition. Refer to Testing for Electrical Intermittents in Wiring Systems.

### Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. This step verifies that the TCC engages when commanded ON by the Scan Tool .

#### DTC P0741 TCC System -- Stuck Off

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Powertrain Diagnostic System Check? | -- | Go to Step 2 | Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls
2 | Did you perform the transmission fluid checking procedure? | -- | Go to Step 3 | Go to Transmission Fluid Check
3 |

1. Install a Scan Tool .
2. Start the engine.

Important: Before clearing the DTCs, use the Scan Tool in order to record the Freeze Frame and Failure Records for reference. Using the Clear Info function will erase the stored Freeze Frame and Failure Records from the PCM.

3. Record the Freeze Frame and Failure Records.
4. Clear the DTCs.
5. With the Scan Tool , observe TCC release pressure.

Does the Scan Tool indicate TCC release pressure is present?

--

Go to Step 5

Go to Step 4

4 |

1. Inspect the following components:

• | The TCC control valve

• | The TCC regulator apply valve

• | The TCC PWM solenoid valve

• | The pressure regulator valve

2. Repair or replace any malfunctioning components.

Refer to Transmission Overhaul in the 4T65-E Section of the Transmission Unit Repair Manual.

Did you complete the repair?

--

Go to Step 7

--

5 |

1. Drive the vehicle above 72 km/h (45 mph) with a TP angle of less than 30%.
2. With the Scan Tool , command the TCC PWM solenoid valve ON and monitor the TCC slip speed display.

Does the Scan Tool indicate the slip speed is within the specified value?

-50 RPM to +50 RPM

Go to Diagnostic Aids

Go to Step 6

6 |

1. Inspect the following components:

• | The TCC control valve for sticking

• | The TCC regulator valve for sticking

• | The TCC PWM solenoid valve and O-ring seal for leaks

• | The TCC PWM solenoid valve filter for plugging

• | The turbine shaft seals for leaks

• | The torque converter clutch

2. Repair or replace the component as necessary.

Refer to Transmission Overhaul in the 4T65-E Section of the Transmission Unit Repair Manual.

Did you complete the inspection or repair?

--

Go to Step 7

--

7 | Perform the following procedure in order to verify the repair:

1. Select DTC.
2. Select Clear Info.
3. Drive the vehicle in D2, D3 or D4 until the TCC is engaged.

• | TP angle must be 4-35%.

• | Time since the last range change must be greater than 6 seconds.

• | The TCC is commanded ON at greater than 50% duty cycle.

• | TCC slip speed must be less than 50 RPM for at least 4 seconds.

4. Select Specific DTC.
5. Enter DTC P0741.

Has the test run and passed?

--

System OK

Go to Step 1