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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2002 🢒 GMC C Sierra - 2WD 🢒 Transmission/Transaxle 🢒 Automatic Transmission - Allison 🢒 DTC P0741

Circuit Description

The transmission control module (TCM) uses data from the engine speed sensor and the input speed sensor to calculate torque converter slip value. The TCM then compares this calculated slip value to a preset value in the TCM calibration.

DTC P0741 is a type B DTC.

Conditions for Running the DTC
    • DTC P0716, P0717, P0721, P0722 and P0743 are not active.
    • The components are powered and ignition voltage is greater than 9.0 volts and less than 18 volts.
    • Engine speed is greater than 200 RPM and less than 7,500 RPM for 5 seconds.
    • The throttle position is in the 10-90 percent range.
    • The transmission must be in forward range.
    • The torque converter clutch (TCC) is enabled.

Conditions for Setting the DTC

DTC P0741 sets when the TCM detects one of the following conditions:

    • A TCC slip value greater than 80 RPM for 15 seconds.
    • The TCC slip speed values indicate a stuck off state.

Action Taken When the DTC Sets
    • The TCM illuminates the malfunction indicator lamp (MIL) during the second consecutive trip in which the Conditions for Setting the DTC are met.
    • DTC P0741 will be stored in TCM history.
    • The TCM freezes shift adapts (DNA).
    • The TCM inhibits TCC engagement.

Conditions for Clearing the DTC

A scan tool can clear the code from TCM history. The TCM automatically clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without failure.

Diagnostic Aids
    • Inspect the wiring for poor electrical connections at the TCM. Inspect for the following conditions:
       - A bent terminal
       - A backed-out terminal
       - A damaged terminal
       - Poor terminal tension
       - A chafed wire
       - A broken wire inside the insulation
    • When diagnosing for an intermittent short or open, massage the wiring harness while watching the test equipment for a change.
    • You may have to drive the vehicle in order to experience a condition.

Test Description

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

  1. This step tests ignition voltage.

    2.

  2. This step tests for TCC enable status.

Step

Action

Value

Yes

No

Schematic Reference: Automatic Transmission Controls Schematics

1

Did you perform the Diagnostic System Check - Automatic Transmission?

--

Go to Step 2

Go to Diagnostic System Check - Automatic Transmission

2

  1. Install the scan tool.
  2. Start the engine.

    3. Important: Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records for reference. The Clear Info function will erase the data.

  3. Record the DTC Freeze Frame and Failure Records.
  4. Clear the DTC.
  5. Using the scan tool, measure ignition voltage.

Is the voltage within the specified range?

9-18 V

Go to Step 3

Go to DTC P0562 for low voltage or DTC P0563 for high voltage

3

  1. Drive the vehicle under normal operating conditions.
  2. Using the scan tool, monitor converter slip speed indicated when a range is attained where the TCC should be applied.

Is the slip speed value at or greater than the specified value when the TCC should be applied?

80 RPM

Go to Step 4

Go to Diagnostic Aids

4

This condition indicates the TCC is mechanically stuck OFF. Inspect for the following conditions:

    • Worn TCC clutch
    • Faulty F solenoid
    • Debris in the TCC valve bore
    • Clogged converter relief passage

Did you find and repair a condition?

--

Go to Step 5

--

5

Perform the following procedure in order to verify the repair:

  1. Clear the DTC.
  2. Start the engine.
  3. Using the scan tool, operate the vehicle under normal operating conditions.
  4. Select Specific DTC.
  5. Enter DTC P0741.

Has the test run and passed?

--

System OK

Go to Step 1