Jeep Cherokee Forum

Jeep Cherokee Forum (https://www.cherokeeforum.com/)
-   Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here (https://www.cherokeeforum.com/f2/)
-   -   Heating & Cooling (https://www.cherokeeforum.com/f2/heating-cooling-161345/)

d_guire792 Feb 3, 2013 02:10 PM

Heating & Cooling
 
I have a problem with the fan with it blowing on defrost no matter what setting it's on but I can turn it off but once in a while I am playing with it and it will kick back on? What would it be causing it to do this?

docmedpros Feb 3, 2013 03:13 PM

so is your question the fan blowing only on one setting or it not moving from defroster vents to the others, if it's the first one then it's the burnt up wires at the switch and blower resistor and/or blower resistor. and if the 2nd then it could be blend door but more than likely the vacuum line is broken in way or another, check the engine bay and trace all your vacuum lines and check for any signs of cracking or holes.

d_guire792 Feb 4, 2013 05:53 PM

It's the first one but it kicks on sometimes to the other settings but it's rare when it does.

RTorrez1 Feb 4, 2013 07:53 PM

If it only blows the defroster, Start by checking for a vacuum leak. Start from the vacuum ball under the bumper passenger side make sure the are not any cracks in it and check all the vac lines all the way to the fire wall.

docmedpros Feb 4, 2013 08:10 PM

since you said it's the blower switching, it's more than likely your resistor and check the wiring plugs like i said before, they usually burn up and fail

VTJeep Feb 4, 2013 08:15 PM


Originally Posted by docmedpros (Post 2290690)
since you said it's the blower switching, it's more than likely your resistor and check the wiring plugs like i said before, they usually burn up and fail

Idk... The resistor wouldn't change the direction of the air flow. If the resistor fails, the air will only work on high. As stated a vacuum leak, or a blend door issue is likely to blame.

d_guire792 Feb 5, 2013 02:06 AM

I will check em but also everything else works fine except the direction which you want it to blow it too.

RTorrez1 Feb 5, 2013 09:16 AM


Originally Posted by docmedpros (Post 2290690)
since you said it's the blower switching, it's more than likely your resistor and check the wiring plugs like i said before, they usually burn up and fail

Wrong! If it was the resistor that would cause it to only blow on high. Not cause it to blow through the defroster.

d_guire792 Feb 10, 2013 09:40 AM

I will check the vacuum then but where would they be located at?

docmedpros Feb 10, 2013 09:42 AM

start with the vacuum ball, and trace the lines.

docmedpros Feb 10, 2013 09:43 AM


Originally Posted by RTorrez1 (Post 2291490)
Wrong! If it was the resistor that would cause it to only blow on high. Not cause it to blow through the defroster.


oh yup sorry, i kept reading it wrong thinking it was the blower not changing speeds. You are correct sir

d_guire792 Feb 10, 2013 10:22 AM


Originally Posted by docmedpros (Post 2301262)
start with the vacuum ball, and trace the lines.

The cruse control ball?

salad Feb 10, 2013 10:58 AM

Yep the vacuum reservoir ball hiding in the front bumper is used to operate cruise and HVAC systems

d_guire792 Feb 10, 2013 12:45 PM

That might be the problem then.....I don't have one there..where can I get one or is there something else I can do instead of using the ball?

docmedpros Feb 10, 2013 01:11 PM

you can make one out of PVC tubing and end caps.


All times are GMT -5. The time now is 07:13 AM.


© 2026 MH Sub I, LLC dba Internet Brands