Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with a sensor that checks the position of a valve in your car's cooling system. It's like a thermometer that isn't working right.
The engine control module (ECM) has detected a high voltage signal from the engine coolant bypass valve C position sensor circuit, indicating a potential issue with the sensor or its wiring.
The P23C5 code is triggered when the ECM receives a signal from the engine coolant bypass valve C position sensor that is higher than the expected range. This could be due to a malfunctioning sensor, wiring issues, or a fault in the ECM itself. The coolant bypass valve is responsible for controlling the flow of coolant in the engine to maintain optimal operating temperature.
• Check Engine Light is on
• Engine overheating
• Poor engine performance
• Faulty engine coolant bypass valve C position sensor
• Wiring issues such as shorts or open circuits
• Faulty ECM
ECM: Engine Control Module, the computer that controls engine functions.
Sensor: A device that detects and measures a physical property and records, indicates, or otherwise responds to it.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the engine coolant bypass valve C position sensor.
• Replace the faulty sensor.
• Repair or replace damaged wiring.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance of cooling system components
• Check wiring and connectors periodically
• Ensure proper coolant levels
Sensor Issue
• Do not ignore the Check Engine Light.
• Address overheating issues promptly to avoid engine damage.
Check with your vehicle manufacturer for warranty coverage on engine components.
This code has been associated with sensor failures in certain vehicle models, often due to wiring issues.
Moderate – Address the issue to prevent potential engine overheating.
Driving with an unresolved engine issue may lead to further damage and is not recommended.
• Engine at operating temperature
• Electrical system functioning properly
The engine coolant bypass valve C is typically located near the engine block or radiator.
Q: Can I drive with a P23C5 code?
A: It's not recommended to drive for extended periods with this code as it may lead to engine overheating.
Q: How do I reset the Check Engine Light?
A: After repairs, you can reset the light using an OBD-II scanner.
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