Heater stuck on defrost?

On many cars/trucks this problem is noticed.
If vacuum is reaching the heater control then the likely problem is that one of the vacuum operated servo "motors" that move the internal doors in the heater box has failed. If no vacuum is at the control, check the line from the engine that goes into the firewall for disconnects, cracks or breaks. Control itself is also suspect but they don't go bad very often.

This details will help.Thanks.

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If you need dis-assembly or replacement instructions for any other auto/car part, or you want to ask question related to your car/truck jeep problem then please leave the comment with your details, so I can provide you the required instructions and solutions.

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