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 the car's computer found a problem with the air conditioner's power relay. It's like a switch that helps turn on the AC, and right now, it's not working right.
The P0EC8 code indicates that the voltage in the A/C power supply relay control circuit is higher than expected.
The A/C power supply relay is responsible for controlling the power to the air conditioning system. When the control circuit voltage is higher than the expected range, the vehicle's onboard diagnostics system triggers the P0EC8 code. This could be due to issues such as a faulty relay, wiring problems, or a malfunctioning control module.
• Air conditioning not working
• Check engine light illuminated
• Unusual noises from the A/C system
• Faulty A/C power supply relay
• Wiring issues such as open or short circuits
• Malfunctioning control module
Relay: An electrical switch that opens and closes under the control of another electrical circuit.
Multimeter: An instrument used to measure voltage, current, and resistance.
• Perform a visual inspection of the A/C relay and wiring.
• Use a multimeter to check the voltage in the control circuit.
• Test the A/C power supply relay for proper operation.
• Replace the faulty A/C power supply relay.
• Repair or replace damaged wiring.
• Reprogram or replace the control module if necessary.
• Multimeter
• OBD-II scanner
• Basic hand tools
$100 - $300
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect and maintain the A/C system.
• Ensure wiring and connections are secure.
• Replace relays at recommended intervals.
Electrical Circuit Issue
• Avoid using the A/C until the issue is fixed to prevent further damage.
• Seek professional diagnostic services if unsure about repairs.
Check with your vehicle manufacturer for warranty coverage on electrical components.
This code has been associated with hybrid and electric vehicles due to their complex electrical systems.
Moderate – While not immediately dangerous, it can affect comfort and lead to further electrical issues.
Operating a vehicle with a malfunctioning A/C system may not be illegal, but it can be uncomfortable and potentially lead to other electrical failures.
• Vehicle at operating temperature
• A/C system activated
The A/C power supply relay is typically located in the vehicle's fuse box, often under the hood.
Q: Can I drive my car with a P0EC8 code?
A: Yes, but the air conditioning may not work, and it could lead to other electrical issues.
Q: How do I reset the P0EC8 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue persists, further diagnosis is needed.
High-End · Full-system diagnostics
A full-system bidirectional platform aimed at advanced DIY users and professional diagnostic workflows.
Network faults often require full-system access instead of a generic code reader alone.
View on Amazon
Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
View on Amazon
Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
View on AmazonThese are optional diagnostic tools, not guaranteed fixes. As an Amazon Associate I earn from qualifying purchases.