Chrysler Repair: 1991 Fifth Ave Short.

Question
Hello Roland,

Thank you for your assistance in advance.  I have a 1991 Chrysler Fifth ave, 3.3 with a short.  The number 12 fuse blows instanly.  This circuit controls  the body computer, electronic cluster(which there really isnt one, its all analog), Radio circuit, glove  box lamp and interior lights as well as cigi lighter.  

I have pretty much disconnected everything and put in new fuse and it still blows.  Was hoping you might have some suggestions as this seems like looking for a needle in a hay stack.  

I also just replaced the heater core.  After two days the short started to occur.  Thought maybe I pinched a wire, but dont see any issues there or any relation between the two.

Any suggestions would be greatly appreciated.

Thanks
Chris

Answer
Hi Chris,
That fuse 12 is the 'ignition off draw fuse' which powers everything needed when the engine is shut down: interior lights, cigar lighters (there are two), memory of the cluster/radio, glove box, under hood and trunk lamps, vanity mirror lamps, black plug of the body control module (pin 16).
The most likely would be a coin that has fallen into one of the cigar lighter sockets or one of the many bulbs has a short in its socket or the bulb itself. It may be that you would have to remove all the ignition-off bulbs and then start putting them back in until the fuse blows. There is no each way that I can see to separate all those different items without getting into some splices. So think back on any bulbs that may have stopped working as a possible location of a bad bulb/socket.
Please read the PS below and respond to it.
Thanks,
Roland