Q: Lost temperature control on hvac

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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.

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