6T30/6T40/6T45 - Automatic Transmission
DTC P0667, P0668, or P0669
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P0667
- Transmission Control Module (TCM) Temperature Sensor Performance
DTC P0668
- Transmission Control Module (TCM) Temperature Sensor Circuit Low Voltage
DTC P0669
- Transmission Control Module (TCM) Temperature Sensor Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The transmission control module (TCM) temperature sensor is located inside of the control solenoid (w/body and TCM) valve assembly which has no serviceable parts. The TCM temperature sensor provides the temperature of the TCM. 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
P0667
* No ISS DTCs P0716 or P0717.
* No OSS DTCs P0722 or P0723.
* The ignition voltage is between 9.0 volts and 18.0 volts.
* The engine speed is greater than 500 RPM for 5 seconds or more.
* DTC P0667 has not set.
* The TCM temperature is between -40 and +150°C (-40 and +302°F).
P0668
* The ignition voltage is between 9.0 volts and 18.0 volts.
* The engine speed is greater than 500 RPM for 5 seconds or more.
* DTC P0668 has not set.
P0669
* No ISS DTCs P0716 or P0717.
* No OSS DTCs P0722 or P0723.
* The ignition voltage is between 9.0 volts and 18.0 volts.
* The engine speed is greater than 500 RPM for 5 seconds or more.
* DTC P0669 has not set.
* The transmission output shaft speed is 200 RPM or greater for 4 minutes or more.
* The TCC slip speed is 150 RPM or greater for 4 minutes or more.
Conditions for Setting the DTC
P0667 - Condition 1
* Vehicle speed is 8 km/h (5 mph) or greater for 5 minutes cumulative.
* Torque converter clutch (TCC) slip speed is greater than 150 RPM for 3 minutes cumulative.
* The TCM internal temperature is between -40 and +21°C (-40 and +70°F) at startup.
* The transmission fluid temperature (TFT) is 70°C (158°F) or greater.
* The TCM internal temperature has changed by less than 2.0°C (3.6°F) in 2 minutes.
* The TFT has increased by 55°C (99°F) since startup.
Condition 2
* Vehicle speed is 8 km/h (5 mph) or greater for 300 seconds cumulative.
* The TCM internal temperature is between 120-150°C (248-302°F).
* The TCM internal temperature has changed by less than 2.0°C (3.6°F) in 2 minutes.
* The TFT is 70°C (158°F) or greater.
* The TFT has increased by 55°C (99°F) since startup.
Condition 3
The TCM internal temperature changes by 20°C (36°F) or greater 14 times over 7 seconds.
P0668
The TCM internal temperature is 254°C (489°F) or greater for 13 seconds or more.
P0669
The TCM internal temperature is -254°C (-425°F) or less for 13 seconds or more.
Action Taken When the DTC Sets
* DTCs P0667, P0668, and P0669 are Type C DTCs.
* The TCM defaults to using the TCM power up temperature sensor value in place of the TCM temperature value.
Conditions for Clearing the DTC
DTCs P0667, P0668, and P0669 are Type C DTCs.
Diagnostic Aids
The TCM temperature sensor is located inside of the control solenoid (w/body and TCM) valve assembly and its output should resemble that of the transmission fluid temperature (TFT) sensor output.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics 6T30/6T40/6T45 - Automatic Transmission
Connector End View Reference
* Component Connector End Views Connector End Views By Name
* Inline Harness Connector End Views Connector End Views By Number
Description and Operation
* Transmission General Description Transmission General Description
* Transmission Component and System Description Transmission Component and System Description
* Electronic Component Description Electronic Component Description
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Programming and Relearning for scan tool information
Circuit/System Verification
1. Ignition ON, Engine OFF. Verify the scan tool TCM Temperature parameter is between -254 and +254°C (-425 and +489°F).
• If not within the specified range, replace the control solenoid (w/body and TCM) valve assembly.
2. Operate the vehicle at 64 km/h (40 mph) for 10 minutes. Monitor the TCM Temperature parameter and the Transmission Fluid Temperature parameter with a scan tool. The TCM Temperature parameter should increase by more than 2°C (3.5°F). Also, the TCM Temperature parameter and the Transmission Fluid Temperature parameter should be within 10°C (18°F) of each other.
• If the TCM Temperature parameter does not increase by more than 2°C (3.5°F) or the TCM Temperature parameter value is not within 10°C (18°F) of the Transmission Fluid Temperature parameter, then replace the control solenoid (w/body and TCM) valve assembly.
3. 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 Verification Tests after completing the diagnostic procedure.
Note: Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection Control Solenoid Valve and Transmission Control Module Assembly Inspection.
* Refer to Control Module References Programming and Relearning for control solenoid (w/body and TCM) valve assembly replacement, setup, and programming.
* Perform the Service Fast Learn Adapts 6T30/6T40/6T45 - Automatic Transmission following all transmission related repairs.