GM Service Manual Online
For 1990-2009 cars only

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 P06AC:  Transmission Control Module (TCM) Power Up Temperature Sensor Performance

DTC P06AD:  Transmission Control Module (TCM) Power Up Temperature Sensor Circuit Low Voltage

DTC P06AE:  Transmission Control Module (TCM) Power Up Temperature Sensor Circuit High Voltage

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

TCM Temperature Sensor

P06AD

P06AD

P06AE

P06AC

Circuit/System Description

The transmission control module (TCM) power up temperature sensor is located inside of the control solenoid (w/body and TCM) valve assembly. The control solenoid (w/body and TCM) valve assembly has no seviceable parts. The TCM power up temperature sensor provides the temperature of the TCM at TCM power up. This temperature reading is used in various shifting and diagnostic routines in the TCM software. This fault is handled inside the TCM and no external circuits are involved.

Conditions for Running the DTC

P06AC - Fail Case 1 and 2

    • No TFT DTCs P0711, P0712, or P0713.
    • No ISS DTCs P0716 or P0717.
    • No OSS DTCs P0722 or P0723.
    • The engine speed is 500 RPM or greater for 5 seconds.
    • The ignition voltage is between 9.0 volts and 19.0 volts.
    • DTC P06AC has not passed this key ON.
    • The TCM power up temperature is between -40 and +150°C (-40 and +302°F).

P06AC - Fail Case 3

    • The engine speed is 500 RPM or greater for 5 seconds.
    • The ignition voltage is between 9.0 volts and 19.0 volts.

P06AD

    • No ISS DTCs P0716 or P0717.
    • No OSS DTCs P0722 or P0723.
    • The engine speed is 500 RPM or greater for 5 seconds.
    • The ignition voltage is between 9.0 volts and 19.0 volts.
    • DTC P06AE has not failed this ignition cycle.
    • The transmission output shaft speed is 200 RPM or greater for 200 seconds or more.
    • The torque converter clutch (TCC) slip speed is 120 RPM or greater for 200 seconds or more.

P06AE

    • The engine speed is 500 RPM or greater for 5 seconds.
    • The ignition voltage is between 9.0 volts and 19.0 volts.
    • DTC P06AE has not failed this ignition cycle.

Conditions for Setting the DTC

P06AC - Fail Case 1

    • Vehicle speed is 8 km/h (5 mph) or greater for 300 seconds cumulative.
    • TCC slip speed is greater than 150 RPM for 300 seconds cumulative.
    • The TCM power up temperature is between -40 and +76°C (-40 and +169°F).
    • The TCM power up temperature has changed by less than 2°C (3.6°F) in 100 seconds.
    • The transmission fluid temperature (TFT) is 70°C (158°F) or greater.
    • The TFT has increased by 55°C (99°F) since startup.

P06AC - Fail Case 2

    • Vehicle speed is 8 km/h (5 mph) or greater for 300 seconds cumulative.
    • TCC slip speed is greater than 150 RPM for 300 seconds cumulative.
    • The TCM temperature sensor is between 76-150°C (169-302°F).
    • The TCM power up temperature has changed by less than 2°C (3.6°F) in 100 seconds.
    • The TFT is 70°C (158°F) or greater.
    • The TFT has increased by 55°C (99°F) since startup.

P06AC - Fail Case 3

The TCM power up temperature changes by 20°C (36°F) or greater 5 times over 7 seconds.

P06AD

The TCM power up temperature is -254°C (-425°F) or less for 10 seconds or greater.

P06AE

The TCM power up temperature is 254°C (489°F) or more for 10 seconds or greater.

Action Taken When the DTC Sets

    • DTCs P06AC, P06AD, and P06AE are Type C DTCs.
    • The TCM allows the vehicle to operate in transmission protection mode.

Conditions for Clearing the DTC

DTCs P06AC, P06AD, and P06AE are Type C DTCs.

Diagnostic Aids

Reprogram the TCM and retest the DTC to see if the DTC resets.

Reference Information

Description and Operation

    •  Transmission General Description
    •  Transmission Component and System Description
    •  Electronic Component 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

Control Module References for scan tool information

Circuit/System Testing

  1. Engine ON, verify the scan tool TCM Power Up Temperature parameter is between -254 and +254°C (-425 and +489°F).
  2. If not within the specified range, replace the control solenoid (w/body and TCM) valve assembly.
  3. Operate the vehicle at 64 km/h (40 mph) for at least 300 seconds while observing the TCM power up temperature sensor and the TCM temperature sensor. Verify that the transmission fluid temperature is within 10°C (18°F) of the TCM temperature sensor.
  4. If not within the specified range, replace the control solenoid (w/body and TCM) valve assembly.
  5. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

       Important: Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection .

    • Refer to Control Module References for control solenoid (w/body and TCM) valve assembly replacement, setup, and programming.
    • Perform the Service Fast Learn Adapts following all transmission related repairs.