Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car has a special part that helps control airflow to the engine, like opening and closing a window. This part got too hot and isn't working right.
The active grille air shutter system helps manage engine temperature and aerodynamics by opening and closing shutters in front of the radiator. Code P05C1 indicates that the module controlling these shutters has detected an over-temperature condition.
The Active Grille Air Shutter (AGAS) system is designed to improve fuel efficiency and engine performance by managing airflow through the radiator. When the module B detects a temperature higher than its operating threshold, it triggers the P05C1 code. This could be due to electrical issues, mechanical binding, or environmental factors causing excessive heat.
• Check Engine Light is on
• Reduced fuel efficiency
• Overheating engine
• Electrical short in the shutter module
• Mechanical obstruction or binding of the shutters
• Faulty temperature sensor within the module
Active Grille Air Shutter: A system that controls airflow through the radiator to improve aerodynamics and engine efficiency.
OBD-II: On-Board Diagnostics, a standardized system for vehicle self-diagnosis and reporting.
• Check for any obstructions in the grille shutters.
• Inspect the wiring and connectors for damage or corrosion.
• Test the temperature sensor in the shutter module.
• Clear any obstructions in the grille shutters.
• Repair or replace damaged wiring or connectors.
• Replace the faulty temperature sensor or shutter module.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Ford F-150
• Regularly inspect the grille area for debris.
• Ensure proper maintenance of electrical systems.
• Avoid driving in extreme conditions without proper vehicle checks.
Cooling System Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Monitor engine temperature while driving.
Check with your vehicle manufacturer as the shutter system may be covered under the powertrain warranty.
Active grille shutter systems have been used in vehicles to improve fuel economy and reduce emissions. Issues with these systems have become more common as they age or in extreme climates.
Moderate – Addressing this issue can prevent further engine performance problems.
Ignoring this code could lead to engine overheating, which may cause significant damage and pose safety risks.
• Vehicle at operating temperature
• Engine running and vehicle stationary
The active grille air shutter module is located at the front of the vehicle, behind the grille.
Q: Can I drive with this code?
A: It's possible to drive short distances, but it's best to get it checked to avoid overheating.
Q: Will this affect my fuel efficiency?
A: Yes, a malfunctioning shutter can reduce fuel efficiency.
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