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 control circuit for one of the car's coolant pumps. It's like when a light switch is broken and can't turn the light on or off.
The engine control module (ECM) has detected an issue with the electrical circuit that controls the third coolant pump (Pump C). This could be due to an open circuit or a failure in the control system.
The P26F4 code is set when the ECM detects an open circuit or malfunction in the control circuit for Coolant Pump C. This pump is part of the vehicle's cooling system, which helps regulate the engine's temperature by circulating coolant. An open circuit means that the electrical path is broken, preventing the pump from operating correctly.
• Check Engine Light illuminated
• Engine overheating
• Reduced engine performance
• Unusual noises from the engine area
• Faulty Coolant Pump C
• Open or shorted wiring in the coolant pump circuit
• Faulty ECM
• Corroded or damaged connectors
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 Coolant Pump C for damage or corrosion.
• Test the coolant pump operation and electrical resistance.
• Check the ECM for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace Coolant Pump C if faulty.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance and inspection of the cooling system
• Promptly addressing any coolant leaks
• Ensuring proper coolant levels
Sensor Issue
• Do not ignore the Check Engine Light.
• Avoid driving the vehicle if overheating occurs.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle manufacturer for warranty coverage on the cooling system components.
This code has been associated with vehicles that have complex cooling systems, often those with turbocharged engines.
High – An unresolved issue can lead to engine overheating and potential engine damage.
Driving with an overheating engine can cause severe damage and may void warranty coverage.
• Engine at operating temperature
• Vehicle stationary
Coolant Pump C is typically located near the engine block or radiator, depending on the vehicle model.
Q: Can I drive my car with the P26F4 code?
A: It's not recommended to drive with this code, as it can lead to engine overheating.
Q: How can I prevent this issue in the future?
A: Regular maintenance and inspection of the cooling system can help prevent this issue.
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