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. This code means the sensor is saying it's too hot.
The control module uses an internal temperature sensor to monitor its own temperature. A 'circuit high' error indicates that the sensor is reporting a temperature that is higher than expected.
The P0669 code is triggered when the Engine Control Module (ECM) detects a high voltage signal from the internal temperature sensor circuit. This could indicate a fault in the sensor, wiring, or the control module itself.
• Check Engine Light is on
• Possible engine performance issues
• Overheating warning
• Faulty internal temperature sensor
• Wiring issues such as short circuits
• Malfunctioning control module
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the control module.
• Test the internal temperature sensor for proper function.
• Replace the faulty internal temperature sensor.
• Repair or replace damaged wiring.
• Replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $600
Moderate
• Ford Focus
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect wiring for damage.
• Ensure proper cooling of the control module.
• Perform routine vehicle diagnostics.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have a professional inspect the vehicle if unsure.
• Avoid driving in extreme temperatures until resolved.
Check with the vehicle manufacturer for warranty coverage on control module components.
This code has been reported in vehicles with aging control modules or poor maintenance history.
Moderate – Addressing this issue promptly can prevent further damage.
Driving with a malfunctioning control module can lead to safety issues and engine damage.
• Engine running
• Normal operating temperature
The control module is typically located in the engine bay or under the dashboard.
Q: Can I drive with a P0669 code?
A: It's not recommended as it can lead to further engine issues.
Q: How do I reset the P0669 code?
A: Use an OBD-II scanner to clear the code, but ensure the issue is fixed first.
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