6T70/6T75 - 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
- Control Module Temperature Sensor Performance
DTC P0668
- Control Module Temperature Sensor Circuit Low Voltage
DTC P0669
- Control Module Temperature Sensor Circuit High Voltage
Circuit/System Description
The transmission control module (TCM) temperature sensor is located inside of the control solenoid valve assembly, which has no serviceable components. 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
* DTC P0101, P0102, P0103, P0106, P0107, P0108, P0171, P0172, P0174, P0175, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0401, P042E, P0658, P0667, P0668, P0669, P06AD, P06AE, P0712, P0713, P0716, P0717, P0722, P0723, P0962, P0963, P0966, P0967, P0970, P0971, P215C, P2720, P2721, P2729, or P2730 is not set.
* Brake torque is not active.
* Engine speed is 400-7500 RPM for 5 seconds.
* Ignition voltage is 8.6-32 V.
* Engine torque signal is valid.
* Throttle position signal is valid.
P0668
* DTC P0668 is not set.
* Engine speed is 400-7500 RPM or greater for 5 seconds.
* Ignition voltage is 8.6-32 V.
P0669
* DTC P0669, P0716, P0717, P0722, or P0723 is not set.
* Engine speed is 400-7500 RPM.
* Ignition voltage is 8.6-32 V.
Conditions for Setting the DTC
P0667
* TCM detects a 20-50°C (36-90°F) or greater difference between the transmission fluid temperature and TCM substrate temperature, which depends on the average of the transmission fluid temperature, TCM substrate temperature, and TCM power up temperature.
* TCM detects an 8-10°C (14-18°F) or greater difference between the TCM power up temperature and TCM substrate temperature, which depends on the average of the transmission fluid temperature, TCM substrate temperature, and TCM power up temperature.
* Above conditions have to be met for 5 minutes within a 6 minute period.
P0668
TCM temperature is -249°C (-416°F) or lower for 1 minute.
P0669
TCM temperature is 249°C (480°F) or greater for 1 minute.
Action Taken When the DTC Sets
* DTCs P0667, P0668, and P0669 are Type B DTCs.
* TCM defaults the TCM substrate temperature to a calculated temperature based on the TCM power up temperature.
Conditions for Clearing the DTC
DTCs P0667, P0668, and P0669 are Type B DTCs.
Diagnostic Aids
The TCM temperature sensor is located inside of the control solenoid valve assembly and its output should resemble that of the transmission fluid temperature sensor output.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics 6T70/6T75 - Automatic Transmission
Connector End View Reference
* Component Connector End Views Sunshade - Left Front
* Inline Harness Connector End Views X110
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 Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON.
2. Verify the scan tool TCM Temperature parameter is between -249 and +249°C (-416 and +480°F).
• If not between -249 and +249°C (-416 and +480°F)
Replace the Q8 Control Solenoid Valve Assembly.
• If between -249 and +249°C (-416 and +480°F)
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
4. Verify the DTC does not set.
• If a DTC sets
Replace the Q8 Control Solenoid Valve Assembly
• If a DTC does not set
5. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
Perform the Reset Transmission Adapts Reset Transmission Adapts following all transmission related repairs.
Control Solenoid Valve and Transmission Control Module Assembly Replacement Service and Repair
Control Module References Control Module References for Control Solenoid Valve Assembly replacement, setup, and programming.