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-   -   AC/Heat works on high only... (http://www.jeepgarage.org/f181/ac-heat-works-on-high-only-64958.html)

Triplecrown 09-02-2013 10:36 AM

AC/Heat works on high only...
 
My 2006 WK has been giving me some trouble regarding the AC/Heat. Sometimes the AC or heat will suddenly turn off or not come on at all, except if it is on the 'high setting'.

I got behind the glove compartment and moved around a plug in /wire harness and it everything works fine. Even then, it sometimes cuts out and its back to working on high setting only.

After examining the 'plug in', there appears to be some melting or burning on the actual 'plug in' that is wired up to the harness, where the 'female' part of the electrical connection is.

What is going on? What is the cause of only being able to use the high setting for the blower? Why is the plug in on the harness, behind the glove box have signs of melting?

I believe it is the 'plug in' harness that connects to the resistor in the blower motor, behind the glove compartment.

Any info helps! Thanks guys!

sonicblaze 09-02-2013 10:44 AM

The most common reason for the fan to only work on high is that resistor board is fried. I've replaced a few in other cars (non-Jeep) for that exact reason.

xJoshxx 09-02-2013 10:57 AM

Re: AC/Heat works on high only...
 
Blower motor resistor is broken internally. Check a Junk Yard. New ones can be $100+

Triplecrown 09-02-2013 11:17 AM

Re: AC/Heat works on high only...
 
Can a bad resistor board cause slight melting anywhere on the 'plug in' that connects to the resistor?

xJoshxx 09-02-2013 11:37 AM

Quote:

Originally Posted by Triplecrown (Post 886369)
Can a bad resistor board cause slight melting anywhere on the 'plug in' that connects to the resistor?

Yes this is because all it does is create a dead short the reduce the power to the fan.

In WJs ust have to cut it off and replace the harness.

Triplecrown 09-02-2013 12:19 PM

Re: AC/Heat works on high only...
 
Quote:

Originally Posted by xJoshxx (Post 886357)
Blower motor resistor is broken internally. Check a Junk Yard. New ones can be $100+

Huh? Are we talking about the same part? I can get them all day long for under $15 bucks.

Triplecrown 09-02-2013 12:24 PM

Re: AC/Heat works on high only...
 
Quote:

Originally Posted by xJoshxx (Post 886378)
Yes this is because all it does is create a dead short the reduce the power to the fan.

In WJs ust have to cut it off and replace the harness.

Thanks! Do I get the resistor with or without Automatic Temp Control?
How do I know which one I have?

Triplecrown 09-03-2013 03:31 PM

Re: AC/Heat works on high only...
 
Update: I replaced the blower motor transistor, and everything seems fine.

2005JGC 09-03-2013 04:22 PM

Re: AC/Heat works on high only...
 
The failure of the resistor is nothing more than it gets hot, and fails. I would always be concerned that the blower motor may be drawing too much current which lead to premature failure of the resistor. The reason your high speed setting worked is because the high speed does not run through any resistor, it is a direct path in and out of the resistor assembly, bypassing any burnt paths through failed resistors. Typically, for a proper repair, as stated previously you do want to cut out the connector and splice in a new connector.

xJoshxx 09-03-2013 05:54 PM

Quote:

Originally Posted by Triplecrown (Post 887022)
Update: I replaced the blower motor transistor, and everything seems fine.

Great!


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