Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble reading the temperature from a sensor inside it. It's like when a thermometer doesn't work right and you can't tell how hot or cold it is.
The P16E4 code indicates that the Powertrain Control Module (PCM), Engine Control Module (ECM), or Transmission Control Module (TCM) has detected a low voltage signal from the internal switch-on temperature sensor circuit.
The PCM/ECM/TCM relies on an internal temperature sensor to monitor the temperature of the module itself. If the sensor circuit reports a voltage that is lower than expected, it triggers the P16E4 code. This could be due to a sensor malfunction, wiring issues, or a problem within the module.
• Check engine light on
• Possible engine performance issues
• Transmission shifting problems
• Faulty temperature sensor
• Wiring issues such as shorts or open circuits
• Faulty PCM/ECM/TCM
PCM: Powertrain Control Module
ECM: Engine Control Module
TCM: Transmission Control Module
• Check for additional codes
• Inspect wiring and connectors for damage
• Test the temperature sensor
• Repair or replace damaged wiring
• Replace faulty temperature sensor
• Replace PCM/ECM/TCM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Chevrolet Malibu
• GMC Sierra
• Cadillac CTS
• Regular maintenance checks
• Ensure proper connections and wiring
• Monitor engine performance
Sensor Issue
• Do not ignore the check engine light
• Get a professional diagnosis if unsure
• Regularly maintain your vehicle
Check your vehicle's warranty for coverage on electronic components.
This code has been associated with sensor and wiring issues in various vehicle models.
Moderate – Addressing this issue can prevent further engine or transmission problems.
Driving with a malfunctioning temperature sensor can lead to engine or transmission damage.
• Engine at operating temperature
• Vehicle stationary
The temperature sensor is located within the PCM/ECM/TCM module.
Q: Can I drive with a P16E4 code?
A: It's not recommended as it can lead to further engine or transmission issues.
Q: How do I reset the check engine light after fixing the issue?
A: You can use an OBD-II scanner to clear the code after the repair.
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