Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car has a special valve that helps control how the engine stays cool. This code means there's a problem with the electrical part that tells this valve what to do.
The P26AD code indicates that the Engine Control Module (ECM) has detected a low voltage condition in the control circuit for the Engine Coolant Bypass Valve B.
The Engine Coolant Bypass Valve B is part of the cooling system that helps regulate engine temperature by bypassing the radiator under certain conditions. The control circuit for this valve is monitored by the ECM, and a low voltage reading suggests an issue with the circuit such as a short to ground, open circuit, or faulty valve.
• Check Engine Light illuminated
• Engine overheating
• Poor fuel economy
• Faulty Engine Coolant Bypass Valve B
• Open or shorted wiring in the control circuit
• Poor electrical connection in the valve circuit
ECM: Engine Control Module, the computer that manages engine functions.
Bypass Valve: A valve that allows coolant to bypass the radiator under certain conditions to help maintain engine temperature.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the voltage and continuity of the control circuit.
• Repair or replace damaged wiring or connectors.
• Replace the Engine Coolant Bypass Valve B if faulty.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II Scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford Fusion
• Chevrolet Malibu
• Toyota Camry
• Regularly inspect coolant system components.
• Ensure proper coolant levels and quality.
• Perform routine maintenance checks.
Sensor Issue
• Do not ignore the Check Engine Light.
• Seek professional diagnosis if unsure.
• Monitor engine temperature regularly.
Check with your vehicle manufacturer for specific warranty coverage related to the cooling system components.
This code is relatively common in vehicles with advanced cooling systems and has been noted in models with electronic coolant bypass valves.
Moderate – While not immediately critical, ignoring this issue can lead to engine overheating and subsequent damage.
Driving with an overheating engine can cause severe damage and may not be covered under warranty if ignored.
• Engine at operating temperature
• Vehicle stationary or at idle
The Engine Coolant Bypass Valve B is typically located near the engine block, connected to the coolant hoses.
Q: Can I drive with a P26AD code?
A: It's not recommended to drive for extended periods with this code active as it can lead to engine overheating.
Q: How do I clear a P26AD code?
A: After repairs, use an OBD-II scanner to clear the code, or disconnect the battery for a few minutes to reset the ECM.
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