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 thinks that one of the fans that cool the engine isn't working properly or is stuck off.
The P2C42 code indicates that the engine control module (ECM) has detected an issue with the performance of the fourth cooling fan, which may not be turning on when needed.
The P2C42 code is triggered when the ECM detects that the fourth cooling fan is not operating as expected. This could be due to the fan being stuck in the off position or not providing the expected performance. The ECM monitors the fan's operation and expects it to turn on under certain conditions to help regulate engine temperature.
• Engine overheating
• Cooling fans not turning on
• Check Engine Light illuminated
• Faulty fan motor
• Blown fuse or relay
• Wiring issues or poor electrical connections
ECM: Engine Control Module, the computer that manages engine functions.
Relay: An electrical switch that opens and closes under control of another electrical circuit.
• Inspect the fan for physical obstructions or damage.
• Check the fan relay and fuse for continuity.
• Test the fan motor for proper operation.
• Replace the faulty fan motor.
• Replace the blown fuse or faulty relay.
• Repair or replace damaged wiring or connectors.
• Multimeter
• Socket set
• Screwdrivers
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Ford F-150
• Regularly inspect cooling fans for debris.
• Ensure electrical connections are secure.
• Maintain proper coolant levels.
Engine Performance
• Avoid driving the vehicle if overheating occurs.
• Regularly check engine temperature gauge.
• Seek professional diagnosis if unsure.
Cooling fans may be covered under powertrain warranty. Check with the manufacturer.
This code has been associated with vehicles that have high mileage or have been driven in hot climates.
High – Engine overheating can cause severe damage if not addressed promptly.
Driving with an overheating engine can lead to engine failure and is unsafe.
• Engine running at normal operating temperature.
• Fans expected to engage during high-temperature conditions.
The cooling fans are typically located at the front of the engine bay, attached to the radiator.
Q: Can I drive with a P2C42 code?
A: It's not recommended, as the engine may overheat, causing further damage.
Q: How do I know if my fan is working?
A: You can visually inspect the fan to see if it turns on when the engine is hot.
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