Tip & How-To about Heating & Cooling

GM - Cars and Trucks with duel zone climate control

Most GM vehicles with separate driver side and passenger side heat and air conditioning can have problems with having heat on one side and cold on the other . The dealer has a computer that can calibrate these systems when the mess up to determine if it has a bad accuator or it's just lost memory. I worked for GM and read thru a test manuel and found that you don't have to have the computer to reset or test this system. If you disconnect the battery for 10 minutes then hook the battery back up , start the vehicle turn the fan switch to medium , do not touch any other part of the system , the climate control will go into a self calibration mode, wait untill it goes thru this self test mode, aproximately 2 to 3 minutes .During this mode you will feel and hear the accuators moving thru their ranges. After they stop changing postions now set your desired temperature for both sides if their is no hard faults (failed parts) the system will resume normal operation . If one or the other still does not blow the correct temperature replace that sides temp accuator repeat the self test mode and you should be fixed.This is a quick and easy way to test your own climate system with out paying the dealer their 100 dollar computer diagnostic fee.

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why does my peugeot 307 sw 1.6 dt. air conditioner blow cold air out of passenger side and hot air out of driver side?

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AC unit blows cold on passenger side and warm on driver side.

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Hope this helps

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