QuestionQUESTION: I have a 1998 GMC Jimmy SLT with electronic climate control blowing hot air no matter the settings. I know the compressor is engaged and the suction is about thiry pounds or so. The problem is the cold air is not getting to the vent ducts.
At one time there was a whirring like a door opening and closing continuously. Then it stopped. Could there be a blown fuse or bad relay?
I also know it has three sensors but have no idea what two of them do. The one I know agout is in the grill and it keeps the a/c off if the ambient is low.
ANSWER: the sound you heard was probably a electronic actuator wearing out. The diverter doors have little electric motors on them to ope. close them. If the heat/cold door actuator is worn it will lock in heat or in btween heat/cold
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QUESTION: I talked to a mechanic here that does our work, but admits to not being an a/c mechanic, said his helper looked up into the vent opening while he operated the controls and thought the blend door was working. He thinks the blend sensor in the dash is defective. Is there any way to check these sensors? Do you think it could be a sensor?
AnswerThere are position sensors on the doors but the only way to check them is to use and ocilliscope ir have a volt/ohm meter that will read petentiometers. It can be checked but the right tools are needed or you may get a false reading.But to answer your queston, yes it could be the sensor itself
