Auto Air Conditioning & Heater Repair: 98 Ford Explorer AC/Heater Problem, automatic temperature control, electrical schematics

Question
I have a 98 Ford Explorer Limited.  It has the Automatic Temperature Control system where you can set the desired temperature and it automatically heats or cools the interior as necessary.  Recently, when I use the automatic function or any of the non-AC buttons like vent, windshield defrost, or heat, it delivers what appears to be maximum heat no matter how low I set the desired temperature.  When I use the AC buttons, like Max AC, the temperature of the air delivered cools down but never really gets cold so I think it is heating up the air and trying to cool it down at the same time.  Do you know how this can be repaired?  I would appreciate any advice you may have.  Thank you.

Answer
My Ford reference material as far as electrical schematics and service manuals is not the great. You are going to need an electrical schematic in order to perform diagnostic tests on the system and if I had one, I would e-mail you a copy.

I would suspect that you have a problem with the DAMPER DOOR CONTROLLER and or damper door vacuum/electric mechanism. But without a schematic, I can't be sure.


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