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 a part in the car that helps control the engine's temperature isn't working right. It's like a thermostat in your house not working properly, so the temperature isn't what it should be.
The P26A3 code is triggered when the Engine Control Module (ECM) detects a problem with the performance or range of the engine coolant bypass valve A.
The engine coolant bypass valve A is responsible for regulating the flow of coolant around the engine to maintain optimal temperature. If the ECM detects that the valve is not opening or closing properly, or is not within the expected range of operation, it will set the P26A3 code.
• Check Engine Light is on
• Engine overheating
• Poor fuel economy
• Faulty engine coolant bypass valve
• Wiring issues in the valve circuit
• Faulty 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 or corrosion.
• Test the engine coolant bypass valve for proper operation.
• Replace the engine coolant bypass valve if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular maintenance of the cooling system.
• Check coolant levels and quality.
• Inspect wiring and connectors periodically.
Engine Performance
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if you're unsure.
• Avoid driving the vehicle if it shows signs of overheating.
Check with your vehicle manufacturer; this part may be covered under the powertrain warranty.
This code has been more common in vehicles with higher mileage or those that have not had regular cooling system maintenance.
Moderate – Address the issue soon to prevent engine overheating.
Driving with an overheating engine can cause severe damage and may be unsafe. Address the issue promptly.
• Engine at operating temperature
• Vehicle stationary
The engine coolant bypass valve is typically located near the engine block, connected to the cooling system.
Q: Can I drive my car with a P26A3 code?
A: It's not recommended to drive with this code as it can lead to engine overheating.
Q: How do I reset the Check Engine Light after fixing the issue?
A: You can use an OBD-II scanner to clear the code after repairs are made.
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