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 of the car's system that helps clean the exhaust is stuck in the 'on' position, even when it shouldn't be.
The P05F6 code indicates that the power relay controlling the exhaust aftertreatment system is not turning off as it should. This can lead to the system running continuously.
The exhaust aftertreatment system is responsible for reducing harmful emissions from the vehicle's exhaust. The power relay control circuit manages the power supply to this system. If the circuit is stuck in the 'on' position, it means that the system is continuously powered, which can lead to unnecessary wear or battery drain.
• Check Engine Light is on
• Unusual battery drain
• Possible decrease in fuel efficiency
• Faulty power relay
• Wiring issues in the control circuit
• Malfunctioning control module
Relay: A device that opens or closes a circuit under the control of another electrical circuit.
Aftertreatment: A system used to reduce harmful emissions from the exhaust.
• Use an OBD-II scanner to confirm the code
• Inspect the power relay for faults
• Check wiring and connections in the control circuit
• Replace the faulty power relay
• Repair or replace damaged wiring
• Reprogram or replace the control module if necessary
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• Chevrolet Silverado
• Ford F-250
• Ram 1500
• Regular maintenance checks
• Ensure wiring is intact and free from corrosion
• Replace relays at recommended intervals
Control Circuit Issue
• Have the vehicle inspected by a professional
• Avoid driving long distances until repaired
Check with the vehicle manufacturer for specific warranty coverage related to emissions systems.
This code has been reported in vehicles with high mileage or those that frequently tow heavy loads.
Moderate – Should be addressed soon to prevent further issues.
Ignoring emission-related issues can lead to failing emissions tests and potential fines.
• Vehicle at operating temperature
• Engine running
The power relay is typically located in the engine bay, near the fuse box or control module.
Q: Can I drive with the P05F6 code?
A: It's possible, but not recommended, as it can lead to further issues.
Q: How do I reset the P05F6 code?
A: After repairs, use an OBD-II scanner to clear the code.
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