Cadillac Repair: Body Control Module, cadillac sedan deville, lh side

Question
QUESTION: I recently purchased a 1998 Cadillac Sedan Deville with 77K miles on it. The engine runs like a top and it's very clean. Like most vehiles, when you open the doors the interior lights come on...this car does it when it feels like it. I've also found that when I turn the car off there is a pulsating of the dashboard and door lights. A couple of times the trunk opened by itself when I parked. During each of these occurrences I heard a clicking sound coming from the trunk area. This is my first Cadillac and I asked around for solutions and most of my friends say it's a "body control modulator" that needs to be fixed. Based on what I've described, what do you think it is? What should I do?

ANSWER: Hi Garry,

      Its easy to condemn a computer if you aren't sure but in this case it could turn out to be the keyless entry module that is also located on the rear panel behind the seats. I believe there is an antenna type wire that you would see on the back of the radio. And it plugs into a 4" by 4" black module located on the LH side of the panel. What I would do is unplug that module multi-wire electrical connector and the keyless entry will quit working but along with that the weird light thing should also stop. If it does then replace the keyless entry module and have your key remotes reprogrammed.

     Hope that helps. Bill

---------- FOLLOW-UP ----------

QUESTION: Your response makes a lot of sense to me, but I'm still confused. When you mentioned, "I believe there is an antenna type wire that you would see on the back of the radio. And it plugs into a 4" by 4" black module located on the LH side of the panel." Do you mean the dashboard or the rear seat panel? I know I sound stupid because the radio is in the dash, but you did say the  module was located on the rear seat panel. I doubt I'd be able to repair it myself, but do you have an idea of what a repair ike this could cost?

Answer
Hi Garry,

      After reading my response I can see why you might be confused.

     The module is located behind the rear seat on the panel on the drivers side. It has 2 wire connectors...1 that looks like an antenna connector like a radio would have and the other is a muli-wire connector. The module is black and aprox. 4" by 4" in size. I wanted you to unplug the multi wire connector and see if the clicking stops.

     As for repair costs I would say 1 hour labor time to diagnose the problem provided it is happening at the shop. Another 1 labor time to replace and program the new module. As for module pricing I'm not sure what the going rate is for that you or the shop will need to contact the dealer or junk yard/auto recycler.

     Hope that clears things up. Bill