2ML70 - 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 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 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 transmission control module 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 engine speed is 0-7500 RPM.
* Vehicle speed is less than 200 km/h (124 mph).

P0667
* DTC P0721, P0722, P0723, P215C, P0658, P0668, P0669, P0712, P0713, P06AD, or P06AE is not set.
* NOT in PARK/NEUTRAL.
* Vehicle speed is greater than 8 km/h (5 mph) and accelerator position is less than 20 percent for 7 seconds.

P0668

DTC P0668 has not failed this ignition cycle.

P0669
* The transmission OSS parameter is greater than 200 RPM for greater than 5 seconds.
* DTC P0669 has not failed this ignition cycle.

Conditions for Setting the DTC

P0667
* 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 8-10°C (46-50°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 -60°C for 60 seconds.

P0669

The TCM temperature parameter is 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 Trans. Fluid Temp. parameter is within 10°C (18°F) of the TCM temperature parameter.

Reference Information
Schematic Reference

Automatic Transmission Controls Schematics (2ML70 - Automatic Transmission)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
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)

Circuit/System Verification

DTCs P0668 and P0669

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 (Control Module References)for Control Solenoid Valve Assembly replacement, programming and setup.