The P0667: PCM/ECM/TCM Internal Temperature Sensor Range/Performance code indicates a performance issue with the internal temperature sensor within the Powertrain Control Module (PCM), Engine Control Module (ECM), or Transmission Control Module (TCM). This sensor monitors the internal temperature of the module to prevent overheating and ensure proper function. A performance issue may result from a faulty sensor, wiring problems, or issues within the module itself.
P0667 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P0667: PCM/ECM/TCM Internal Temperature Sensor Range/Performance |
| Is it serious? | Yes, as it can affect the control module’s ability to monitor internal temperature, possibly leading to overheating and malfunction. |
| Possible causes | – Internal temperature sensor performance issue in PCM/ECM/TCM – Faulty sensor – Wiring issue |
| How to diagnose? | – Test internal temperature sensor performance – Inspect wiring and connectors – Replace PCM/ECM/TCM if necessary |
P0667 Meaning
The P0667 code indicates that the control module (PCM/ECM/TCM) has detected that its internal temperature sensor is not operating within its expected range. This sensor ensures that the module’s temperature remains within safe operating limits. If the sensor is underperforming or malfunctioning, it can lead to incorrect temperature readings, which could result in overheating and control module failure.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for additional related codes, especially those concerning the PCM, ECM, or TCM, which may provide further insights into the sensor issue. | OBD-II Scanner |
| Test the Internal Temperature Sensor Performance | Use a diagnostic tool or multimeter to test the functionality of the internal temperature sensor within the control module, ensuring it is reading within the manufacturer’s specified range. | Diagnostic Tool, Multimeter |
| Inspect Wiring and Connectors | Check the wiring and connectors leading to the control module for signs of damage, loose connections, or corrosion that could interfere with the sensor’s performance. | Flashlight, Multimeter |
| Test the PCM/ECM/TCM Internal Temperature Sensor | If accessible, test the internal temperature sensor directly within the control module. Ensure the sensor provides accurate temperature readings. Replace if faulty. | Diagnostic Tool, Multimeter |
| Replace the PCM/ECM/TCM if Necessary | If the internal temperature sensor is found to be defective and integrated into the control module, replacing the PCM/ECM/TCM may be necessary to restore proper function. | Replacement PCM/ECM/TCM, Tools |
| Clear the Code and Test | After repairs, clear the code using an OBD-II scanner and test the vehicle to ensure the internal temperature sensor and module are functioning properly. | OBD-II Scanner, Vehicle Manual |
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