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 the part of the car that helps control the engine's temperature. It's like a thermostat in your house, but for your car's engine, and it might be stuck or not working right.
The code indicates that the control circuit for the engine coolant bypass valve C is experiencing a high voltage condition.
The engine control module (ECM) monitors the voltage in the control circuit of the engine coolant bypass valve C. If the voltage is higher than expected, the ECM sets the P26B9 code. This can affect the engine's ability to regulate temperature efficiently, potentially leading to overheating or inefficient operation.
• Check Engine Light is on
• Engine overheating
• Poor fuel economy
• Faulty coolant bypass valve C
• Wiring issues such as short to voltage
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the coolant bypass valve C for proper operation.
• Replace the faulty coolant bypass valve C.
• 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 Fusion
• Chevrolet Malibu
• Toyota Camry
• Regular maintenance checks
• Ensure coolant levels are adequate
• Inspect wiring and connectors periodically
Sensor Issue
• Do not ignore the Check Engine Light.
• Get the vehicle inspected by a professional.
• Avoid driving the vehicle if it shows signs of overheating.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code has been associated with issues in newer vehicles equipped with advanced engine cooling systems.
Moderate – Addressing this issue promptly can prevent further engine damage.
Driving with an overheating engine can cause severe damage and is unsafe.
• Engine at operating temperature
• Vehicle parked with ignition on
The coolant bypass valve C is typically located near the engine block, integrated into the cooling system.
Q: Can I drive my car with a P26B9 code?
A: It's not recommended to drive with this code active as it can lead to engine overheating.
Q: How do I reset the Check Engine Light after fixing the issue?
A: Use an OBD-II scanner to clear the code after repairs are completed.
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