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sandos17 09-03-2008 10:56 AM

A/C only works on Max
I just bought my first Jeep (05 Willy) after many yrs of waiting.......I noticed that the A/C only works on Max. Cold on top vents but medium cold on the bottom. When I change it to Max - 1 no air comes up from the top or bottom. I hear the fan working and the compressor. any ideas?

sandos17 09-03-2008 10:59 AM

I've heard that this might be caused by the resistors a the blower motor (Under dash). I'm hoping since it's about 50 bucks....

Jerry Bransford 09-03-2008 11:08 AM

The resistor pack is what gives the fan its multiple lower fan speeds. It uses resistors to reduce the voltage to the fan motor for all of the lower fan speeds, with no resistor used for the highest speed fan setting. Can you hear the fan running at the lower settings or just the highest setting? If it runs at lower speeds too but just no air comes out of the vents, it's likely you have bad door controller which is how air is routed between the defroster, dash vent, and floor vents. Older TJs like mine use vacuum to control alll that but newer TJs like yours do it differently and I'm not familiar with that part of the newer TJ's HVAC system.

It'd be a bad resistor pack only if one or more of the lower fan speeds were inoperative with the highest fan speed working ok.

Jrzymilitia 09-03-2008 11:30 AM

Usually when the speed controls wont change the first thing that goes is the actual controller. Is it digital or analog?

sandos17 09-03-2008 12:58 PM

I hear the fan running at lower settings. Is there any way of knowing for sure if that's it?

sandos17 09-03-2008 12:59 PM

The controller (knobs) are Analog:confused:. Not sure if that's what ur asking.

Jerry Bransford 09-03-2008 01:27 PM

It's a safe bet the HVAC controls in a Wrangler are "analog". :D

And Sandos, with everything off but the ignition so the fan can be heard, if you can hear something that varies in pitch with your fan speed control, you can bet it's the fan. :)

sandos17 09-03-2008 03:15 PM

thx Jerry. Ur the man:cool:

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