Skip the auto shop - Our mechanics make house calls

Q: Lost temperature control on hvac

asked by on

Last week I disconnected the battery to clean posts and connectors. Since then I cannot control the temperature. I don't have the electronic push button system. Mine is the knob selectors. I first noticed that it wouldn't adjust for a cooler temperature in the cold weather we were having. Toward the end of the week it had warmed up. I thought I would try the ac. I turned the knob to cold setting and then selected Max Cool. Nothing but very hot air. Turned it off. When I got home, I left the temperature selection to cold. Now I have nothing but cold air. I read somewhere that this could be a simple reset issue after having disconnected the power. But I don't know if that was referring only to the electronic push button system. What I read indicated I will need a mechanic for this step. Does the reset also apply to my climate control system?

Hello, and thank you for writing in. Without knowing the make and model of your vehicle, it is difficult to determine what kind of electrical components we are working with. In general, when the battery is disconnected it can mess with settings with the radio and other presets. In addition it may cause the climate control to become confused about what setting it is set to. Typically regardless of what brand of vehicle you have, it can either be reprogrammed or reset. There are a couple of things you can try before resorting to a technician. They include (depending on make and model) key cycling (turning the key to the on position, or turning the vehicle completely on 3-5 times), driving a certain amount of miles, turning the climate control off and on a certain number of times, or unplugging the battery for a certain amount of time. Again these are tricks used by several car manufactures, and the exact procedure will depend on you specific vehicle. If all else fails, contact our service department to schedule an appointment.

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

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: Climate buttons - 2014 Ford Edge

Ford has admitted there are issues with the climate control on some of these vehicles. At first it sounds like a wiring issues. There may be a short or fault in the circuit somewhere in the system. These issues are...

Q: Car battery light constantly goes on and off.

Hello. The fact that the car struggles when you take the jumper cables off suggests that the battery is not able to maintain a charge on its own. I would recommend checking the alternator and the voltage regulator as these...

Q: Problem with cabin vents in Nissan Qashqai 2013 1.5Dci (Dual climate control)

Hello. Thank you for writing in. The climate control utilizes a duct system and blend doors to control the temperature of air entering the cabin. If these blend doors are not mixing the correct air supply than the air entering...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
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.