Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer has a sensor that checks how hot it is inside the computer. This sensor seems to be stuck and isn't giving the right information.
The Powertrain Control Module (PCM), Engine Control Module (ECM), or Transmission Control Module (TCM) uses an internal temperature sensor to monitor its own temperature. If the sensor signal is stuck, it means the sensor is not changing its readings as expected.
The P16D8 code indicates that the internal temperature sensor within the PCM, ECM, or TCM is not providing variable readings as expected. This could be due to a fault in the sensor itself, wiring issues, or a malfunction within the module.
• Check Engine Light is on
• Vehicle may go into limp mode
• Possible erratic engine or transmission behavior
• Faulty internal temperature sensor
• Wiring issues or poor connections
• Faulty PCM/ECM/TCM
PCM: Powertrain Control Module
ECM: Engine Control Module
TCM: Transmission Control Module
• Use an OBD-II scanner to confirm the code
• Inspect wiring and connections to the PCM/ECM/TCM
• Test the internal temperature sensor functionality
• Repair or replace faulty wiring or connections
• Replace the internal temperature sensor
• Replace the PCM/ECM/TCM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $1000
Moderate
• Chevrolet Cruze
• Buick Encore
• GMC Terrain
• Regularly inspect and maintain vehicle wiring
• Ensure PCM/ECM/TCM is not exposed to extreme temperatures
• Perform regular vehicle diagnostics
Sensor Issue
• Do not ignore the Check Engine Light
• Have the vehicle inspected by a professional
• Avoid driving in extreme conditions until fixed
Check if the vehicle's powertrain warranty covers PCM/ECM/TCM issues.
This code has been associated with vehicles experiencing internal module failures due to temperature sensor faults.
Moderate – While the vehicle may still be drivable, it's important to address the issue to prevent further damage.
Driving with a malfunctioning PCM/ECM/TCM can lead to unexpected vehicle behavior, which may be unsafe.
• Engine at operating temperature
• Vehicle in a safe location for diagnostics
The PCM/ECM/TCM is usually located in the engine bay or under the dashboard.
Q: Can I drive with a P16D8 code?
A: It's not recommended as it may lead to further issues. Have it checked as soon as possible.
Q: What happens if I ignore the P16D8 code?
A: Ignoring the code can lead to engine or transmission problems and potentially more costly repairs.
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