Skip the auto shop - Our mechanics make house calls

Q: Temperature rises when air or heat turned off

asked by on

When I have the air conditioner or heater on, the temperature stays normal. But when I turn the air or heat off, the temperature rises.

A: Hello. If the engine starts to overheat wit...

Hello. If the engine starts to overheat with the heater off or without the AC on, then it is usually caused by an issue with air flow through the radiator. You may have a failing fan relay or a circuit issue within the wiring. A voltage meter would need to be used to determine where the voltage is being lost. I would enlist the help of a certified mechanic, like one from YourMechanic, to inspect for any electrical problems and replace any bad fuses or relays.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Vehicle wont start

The fuel system pressure should be checked to see if it is within specifications to start the vehicle and open the injectors. If the pressure is too low or no pressure then check the fuel pump connector and if it...

Q: Faulty radiator

Thanks for writing in. There are many things that can cause thermostat or water pump problems, from broken serpentine belts, to air bubbles in the coolant lines and more. A faulty radiator is not very common. However, if it's...

Q: Spark plug wire

Hello, thank you for writing in. Spark plug wires are typically not universal, and you want to be careful using a separate set of plugs off of another vehicle. Not only are they designed to work with certain plugs, they...

Related articles

P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.