Chrysler Repair: 1992 Dodge Shadow electrical problem, amp fuse, fuse box

Question
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Followup To
Question -
 Did I mention that I disconnected the radio and still blew fuses so I don't think it is the radio.

Thanks
Rock

I have a 1992 Dodge Shadow that is blowing fuses.  When I replace the fuse, it blows immediately.  The circuit is 10 amp fuse which operates (Dome, Cargo, Key in and Glove Box Lights, Radio Memory, Time Delay, Power Mirrors, and underhood lamps.  How can I track this problem?  Do you have schumatic for my car?  Any hint of where I should start?

The problem first was draining my battery (would go dead ever 2-3 days.  I attached clip of test light to negative battery terminal and put the tip on the negative battery post and it light. Pulled fuses from fuse box till light went out to determine whic circuit to test.  I then removed the radio looking for bare wire but couldn't find one.  When I reinstalled the radio, the fuse immediately blew.  Now I can't replace fuse without blowing.  Can you help me with this?

Thanks
Rock
Answer -
Hi Rock,
The fact that the radio being plugged in causes the fuse to blow is pretty strong evidence that the radio is the culprit. The fuse supplies a wire at the radio that is the pink one at pin 1 of the gray connector which is the supply for the memory that maintains the presets on you push buttons. So if there is no obvious short in that wire you could open the radio and examine the internal wiring for a short or a blown capacitor and replace that. If you had an ohmmeter you could verify that the pink wire input is indeed shorted by measuring between the pink wire and the radio case. If it reads less than 2 ohms that would indeed blow the fuse when you plug it in. If you don't mind loosing the presets then you could just cut that wire and insulate the tip of the incoming side against a short. I have the wiring diagrams, but I think you found the problem.
Roland

Answer
Hi Rock,
No that is not what I understood to be the situation. Because removing the radio turned off the test light the first time you tried it, I would suspect a short to ground in the pink wire that is coming in on the supply side of the radio's gray plug in. Another possibility is that the main splice for the pink wire, where all the other wires spread from it near the fuse box to get to the all the lights etc. that are powered by that #13 fuse, has a bare spot in its insulation so that is where it is grounding the fuse. The splice is very near the fuse box from what I can see by the drawing in the wiring diagram manual. So try and find the pink wire that exits the fuse box near #13 and goes to a nearby "ball" of 6 pink wires and see if there is a bare spot in its insulation. If not, then trace the pink wire that is routed to the radio to see if its insulation is shorted to a grounded metal surface.  It you want to test the situatition use an ohmmeter to measure from the cold side of the #13 socket when the fuse is removed to see what the resistance reading is to ground. All the courtesy and dome lamps will have to be with their switches in the off position when you do this measurement because the bulbs only have a resistance of a few ohms. It is possible that the problem is with one of the bulb wire leads or one of the bulbs itself could be shorted in its socket but then why would unplugging the radio be the initial solution?
So focus on the splice and the pink wire to the radio plug, and if you can't find any short then you will have to try removing all the courtesy bulbs and checking each of their supply wires. An ohmmeter is the way to do this rather than using a new fuse as a testor. It gets a bit pricey. I can give you an inventory of every item that is supplied by the pink wire if you don't have it already.
Roland