P0668

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 Descriptor
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

Circuit/System Description

The transmission control module (TCM) temperature sensor is located inside of the transmission control module. The transmission control module is located within the control solenoid valve assembly and is not serviced separately. The TCM temperature sensor provides the transmission control module temperature. This temperature reading is used in various shifting and diagnostic routines in the transmission control module software.

Conditions for Running the DTC

* The system voltage is 11 to 18 V.
* Engine speed is greater than 450 RPM.
* DTC P0722 or P0723 is not set.

P0667
* DTC P0711, P0712, P077B, or P215C is not set.
* DTC P0667 has not passed this key ON.
* The TCM temperature is at least -39°C (-38°F) and no more than +149°C (+300°F).

P0668

DTC P0668 has not failed this ignition cycle.

P0669
* The transmission OSS parameter is greater than 200 RPM for greater than 200 seconds.
* DTC P0669 has not failed this ignition cycle.

Conditions for Setting the DTC

* The difference between the TCM temperature and Trans. Fluid Temp. is greater than 15-50°C (59-122°F), depending on the highest of the Trans. Fluid Temp., TCM temperature and TCM power up temperatures.
* The difference between the TCM power up temperature and TCM substrate temperature is greater than 15-50°C (59-122°F), depending on the highest of the Trans. Fluid Temp., TCM temperature and TCM power up temperatures.
* The above conditions have to be met for 5 minutes.

P0668

The TCM temperature parameter is less than or equal to -60°C (-76°F) for greater than 60 seconds.

P0669

The TCM temperature parameter is greater than or equal to 160°C (320°F) for greater than 60 seconds.

Action Taken When the DTC Sets

DTCs P0667, P0668 and P0669 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0667, P0668 and P0669 are Type B DTCs.

Diagnostic Aids

This DTC may be set due to an overheating condition. The system is operating normally when the Transmission Fluid Temperature parameter is within 10°C (18°F) of the TCM temperature parameter.

Reference Information
Schematic Reference

Automatic Transmission Controls Schematics Electrical Diagrams
Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1
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

Verify that DTC P0667, P0668 or P0669 is not set.

If the DTC is set, program the Q8 control solenoid valve assembly. If the DTC resets, replace the Q8 control solenoid valve assembly.

Component Testing

Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection Control Solenoid Valve and Transmission Control Module Assembly Inspection.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

* Control Module References Programming and Relearning for Control Solenoid Valve Assembly and Transmission Control Module Assembly replacement, programming, and setup.
* Perform the Reset Transmission Adapts Programming and Relearning following all transmission related repairs.