Chevrolet Trax: DTC P0667, P0668, OR P0669

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 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.
• Engine torque signal is valid.
• Ignition voltage is 9-32 V.
• Engine speed is 400-7,500 RPM for 5 s.
• Throttle position signal is valid.
• Runs continuously when above conditions are met.

P0668

• DTC P0668 is not set.
• Ignition voltage is 9-32 V.
• Engine speed is 400-7,500 RPM for 5 s.
• Runs continuously when above conditions are met.

P0669

• DTC P0669, P0716, P0717, P0722, or P0723 is not set.
• Ignition voltage is 9-32 V.
• Engine speed is 400-7,500 RPM for 5 s.
• Runs continuously when above conditions are met.

Conditions for Setting the DTC

P0667

• TCM detects a 20-50ºC (36-90ºF) 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 a 8-10ºC (14-18ºF) 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 min within a 6 min period.

P0668

TCM internal temperature is 254ºC (489ºF) or greater for 1 min.

P0669

TCM internal temperature is -254ºC (-425ºF) or less for 1 min.

Action Taken When the DTC Sets

• 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

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. During a road test, the TCM temperature should steadily increase to a normal operating temperature, and then stabilize.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics (Encore, MH8 or MHB) , Automatic Transmission Controls Schematics (Trax, MH8 or MHB)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

• Inline Harness Connector End Views (Encore) , Inline Harness Connector End Views (Trax)

Description and Operation

• Electronic Component Description
• Transmission Component and System Description
• Transmission General 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 (LUV) , Powertrain Diagnostic Trouble Code (DTC) Type Definitions (2H0)

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.
2. Verify the scan tool TCM Temperature parameter is between -254 and +254ºC (-425 and +489ºF).

If not between -254 and +254ºC (-425 and +489ºF)

Replace the Q8 Control Solenoid Valve Assembly.

If between -254 and +254ºC (-425 and +489ºF)

3. Verify the scan tool TCM Temperature parameter increases greater than 2ºC (3.6ºF) after operating the vehicle at 64 km/h (40 mph) for 10 min.

If the temperature does not increase greater than 2ºC (3.6ºF)

Replace the Q8 Control Solenoid Valve Assembly.

If the temperature increases greater than 2ºC (3.6ºF)

4. Verify the scan tool Transmission Fluid Temperature and TCM Temperature parameters are within 20ºC (36ºF) of each other.

If the temperatures are not within 20ºC (36ºF)

Replace the Q8 Control Solenoid Valve Assembly.

If the temperatures are within 20ºC (36ºF)

5. 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.
6. Verify the DTC does not set.

If the DTC sets

Replace the Q8 Control Solenoid Valve Assembly.

If the DTC does not set

7. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Perform the Transmission Adaptive Values Learn following all transmission repairs
• Control Module References - for Control Solenoid Valve Assembly replacement, programming and setup

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