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 with a part that helps control air going into the engine. It's like a window that opens and closes to let air in, and the computer can't tell if it's working right.
The active grille air shutter system helps control airflow to the engine for better fuel efficiency and temperature management. The position sensor monitors the shutter's position, and a 'circuit high' code indicates an issue with the sensor's electrical circuit.
The P059C code is triggered when the Powertrain Control Module (PCM) detects a high voltage signal from the Active Grille Air Shutter A Position Sensor circuit. This can indicate an electrical issue such as a short circuit, faulty sensor, or wiring problem.
• Check Engine Light is on
• Reduced fuel efficiency
• Engine overheating in extreme cases
• Faulty position sensor
• Short circuit in the wiring
• PCM malfunction
PCM: Powertrain Control Module, the car's computer that controls engine functions.
Circuit High: An electrical circuit issue where the voltage is higher than expected.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the position sensor for proper voltage and resistance.
• Replace the faulty position sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Ford F-150
• Regularly inspect wiring and connectors.
• Keep the grille area clean and free of debris.
• Schedule routine maintenance checks.
Sensor Issue
• Don't ignore the Check Engine Light; have it checked soon.
• Regular maintenance can prevent such issues.
• Consult a professional if unsure about repairs.
Check with your vehicle's manufacturer for specific warranty coverage related to emissions and engine components.
The use of active grille shutters has increased in modern vehicles to improve aerodynamics and fuel efficiency, leading to more frequent occurrences of related codes.
Moderate – Address the issue to prevent potential engine performance problems.
Driving with a malfunctioning grille shutter can lead to increased emissions and reduced vehicle efficiency, which may not comply with local environmental regulations.
• Engine at operating temperature
• Vehicle in a controlled environment
The active grille air shutter is typically located at the front of the vehicle, behind the grille.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to reduced fuel efficiency and possible engine overheating.
Q: Can I drive my car with this code?
A: You can drive the car, but it's best to address the issue soon to avoid potential engine problems.
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