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 there is a problem with the sensor that tells the car's computer the position of a valve that helps control the engine's temperature.
The engine coolant bypass valve is part of the system that helps regulate the engine's temperature. The position sensor tells the car's computer where the valve is, so it can adjust as needed.
The P23C3 code is triggered when the Engine Control Module (ECM) detects a malfunction in the circuit of the Engine Coolant Bypass Valve C Position Sensor. This sensor provides feedback to the ECM regarding the position of the coolant bypass valve, which is crucial for maintaining optimal engine temperature and efficiency.
• Check Engine Light illuminated
• Engine overheating
• Poor fuel economy
• Erratic engine temperature readings
• Faulty coolant bypass valve position sensor
• Wiring issues such as shorts or open circuits
• Corroded or damaged connectors
• Faulty Engine Control Module (ECM)
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connectors for damage
• Test the coolant bypass valve position sensor
• Check the ECM for faults
• Replace the faulty coolant bypass valve position sensor
• Repair or replace damaged wiring or connectors
• Reprogram or replace the ECM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance checks
• Ensure proper coolant levels
• Inspect wiring and connectors periodically
Sensor Issue
• Address the issue promptly to avoid engine damage
• Consult a professional mechanic if unsure
Check vehicle warranty for coverage on emissions and engine components.
This code is relatively uncommon and typically associated with newer vehicle models that have advanced engine temperature management systems.
Moderate – Should be addressed soon to prevent potential engine overheating.
Ignoring this code can lead to engine damage, which may not be covered under warranty if neglected.
• Engine at operating temperature
• Vehicle in a safe, stationary position
The coolant bypass valve is typically located near the engine's thermostat housing.
Q: Can I drive with a P23C3 code?
A: It's not recommended to drive for long periods with this code, as it may lead to engine overheating.
Q: How do I reset the Check Engine Light?
A: After repairs, use an OBD-II scanner to clear the code and reset the light.
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Fitment Required · Vehicle-fitment part
Relevant when coolant-temperature and warm-up faults indicate a thermostat-related issue.
Coolant-temperature and warm-up faults often lead to thermostat testing and replacement.
Thermostats are vehicle-specific and should be matched by engine and housing style.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.