Sounds like a bad relay. Maybe this will help?

http://www.jeepforum.com/forum/showthread.php?p=7644706

Max :cheers2:

 

I had the same problem in my 03 jeep grand cherokee.I am no mechanic but i did it myself.It is under the passenger side headlight.but there is a plastic gaurd under the headlight so instead of removing the the feder and the bumber i just drilled a couple of holes in the plastic and snapped the rest of the plastic with a pair of chanel locks.you should be able to see the relay it is held on by two bolts.it was easy to do.I was a bit leary of snapping the plastic cover though i talked to a couple of mechanic and the said the usually hit it with an air hammer. I did almost 3 years ago and havent had any problems with that relay since.Good luck

 

Picked up a new relay for the wife's WJ from NAPA for $60:thumbdown:but it was the only outfit in town that had one in stock. Based on previous threads, this seemed like a pretty easy job. Instead of using a hole saw or snapping plastic, I used a torch and heated up a knife to slice through the header panel. Clean cuts, no shavings or cracked plastic anywhere. It worked so well that I was able to reuse the piece I cut out, and refastened it with some 90 degree brackets that I flattened with a hammer. A little bead of silicone around the cut out and no she's sealed pretty good (slight cob-job in technique, but hey, whatever works!) Other than that, My father-in-law, who is a long time marine mechanic guru and all-around handy fellow, advised me to put something called "heat-sink compound" on the bottom of the new relay before installing. It's pretty ingenious stuff...Takes the heat from the realy and passes through the compound into the frame metal, all while insulating the relay. I guess this is how the relay usually fails -- to much heat. Anyway thanks for the advice all! She now has her Rig back on the road, and toting our newborn around town safely again.:thumbsup: