KJ 2007 A/C not blowing after some time

sdg · **Joined:** Thu Jan 16, 2014 7:51 am **Posts:** 20

Good day,

Apologies if this has been resolved before -- I couldn't find a definitive root cause / fix for such an issue.

My 2007 KJ (3.7l) would stop blowing air through the dash A/C vents after 15-20 minutes of working. It doesn't matter whether the A/C is on or off, whether it's on hot or cold, whether it's on recirculate or at any other position, whether it's idle or speeding on the highway.

The 1/2/3/4 positions all work -- before it stops blowing, if I change the "blowing strength" it does feel the difference. After it stops blowing, the noise would still change but no air comes out from any vent.

I've replaced the blower motor resistor, to no avail. I don't have a cabin air filter, the iron mesh next to the glovebox compartment is clean.

Should I start thinking of disassembling the dash to get to the recirculate door and the blower motor itself?

Thanks a lot,
SDG

wheeee32 · **Posted:** Fri Nov 07, 2014 8:21 am

I thought the blower motor was right under the glove box. Is that piece not it? The piece that you can easily see if you look below the glove box that is out in the open.

sdg · **Joined:** Thu Jan 16, 2014 7:51 am **Posts:** 20

wheeee32, the blower motor is indeed there, unfortunately my weekend schedule did not allow me to get under the glove box. Thanks for the encouragement, I will check it out when I have an hour free (probably some morning this week); I found a good guide here: http://www.jeepkj.com/forum/f202/how-re ... bly-35659/

--SDG

sdg · **Joined:** Thu Jan 16, 2014 7:51 am **Posts:** 20

Just to say I'm still working on this; despite the howto, I couldn't take the motor off. I'll be looking for help next week.

sdg · **Joined:** Thu Jan 16, 2014 7:51 am **Posts:** 20

(I've also posted this in another thread) So, replaced pressure sensor (the guy in the shop didn't tell me which one), flushed core, cleaned filter (the one below the plastic windshield/wipers base), recharged with freon. Now it blows your head off. Let's see how it develops in the next weeks...

mass-hole · **Posted:** Wed Jul 01, 2015 11:08 am

I'm no expert, but if you can still hear the fan when you change the fan speed setting after the air stops blowing, it must be the door obstructing the flow.

McTudor · **Posted:** Wed Jul 01, 2015 3:04 pm

Does the reduction in airflow also occur with the heating system?

If it is only the A/C then you could have a clogged evaporator. Over time the fins can collect dust, pollen, or any number of crud into it. As your system is running it will form condensate on the evaporator. If the fins are dirty it will not allow the condensation to run off the coil and out of the drain. After a few minutes the moisture will start to freeze on the coil restricting the airflow.

If you run the A/C for and you start getting less airflow, turn the jeep off for 20 minutes. If you have the normal airflow after a restart, this may be your issue.

I have had this issue on my jeep also. I see the same problem on high humidity days vs. dry days.

Unfortunately the only way to solve this is to tear the dash apart and clean the fins on the evaporator.

KJ 2007 A/C not blowing after some time

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