I've had this '09 Grand Cherokee for about 6 months and in the last 3 months the AC blower has shut off 4-5 times. It will be fine, then stop blowing -- but if I drive real fast, I can feel cold air drafting out of the vents. Then for no reason , after days or weeks, it will start blowing again.

Its now been out for several weeks and I assumed I had one of those melted connectors everyone is warning about. But then today I started the car and cold air started bellowing out again.

So before I go tearing stuff apart and making a mess, does anyone have any ideas why the blower would cut in and out sporadically like this? There seem to be a lot of AC issues with these jeeps but they are all a little bit different.

Its getting very hot and sweaty here in New Orleans, I would really love to figure this one out!

Thanks

 

The plug at the blower resistor can be melted.

 

I know that is a notorious problem on these cherokees but I would think that once the plug melts it would shut off the blower until replaced.

Im wondering if there is some other component that might cause this behavior.

 

A melted plug can give you an intermittent connection. Try wiggling the plug and see if it makes a difference.

 

Had the same issue on my 99. Plug looked fine until it was removed, then u could see the inside was all burnt. Replaced the plug and its been fine since. I could wiggle the plug and the blower would come on and off....give that a try to confirm.

 

Yep, same thing happened to me. I took the resistor module out (under the passenger side dash), took it apart and found it burnt. I actually had a diode become unsoldered!! I checked the diode and it was ok....soldered back in, resoldered in new heavier duty wire. Spliced in and I haven't had a problem since. It beat having to buy a new module....
By the way, the plug was so burnt I couldn't remove it, it was melted to the module housing. Had to basically cut it out and hardwire it to the Ckt board inside the module. I added a quick disconnect in case it needed to be removed another time.

Fuuny how the timing on these things happen.....sweltering heat in N.O. It happened to me when it was 5 degrees below zero and wouldn't blow heat!!!

 

This was the problem on mine.http://www.wjjeeps.com/blower_motor.htm