Hello All.

I had an interesting experience yesterday while doing some routine work in an area I rarely if EVER get my eyeballs on. In the area in the boot, the spare tire compartment, under the floor, deck or boot floor panel I looked down to see that due to heat,,, the shielding/insulation for the main power cable had dried, melted and fallen away on a segment of the cable. The MEGA Fuse connector or High Power Protection Module (HPPM)... It's what I would guess is a 0 gauge wire/cable that runs from the boot, under the car (I think), to the false bulkhead (bolt) connection on the RH side. The frame out for the ecu/m, fuse box and other things.... that connection then goes to the starter and alternator. The false bulkhead. Basically the MAIN power cable/wire for the car.

Anyways, with the car running, the cable was blazing hot. No TEMP measurement was taken but it was hot to a point that CANT be good. Too hot to touch. Because of age and corrosion, being exposed (in my case) the cable was producing enough resistance to get hot enough to break down and crumble it's plastic/rubber insulation. This was found at the last inches before the (HPPM) in the boot. This amount of heat was produced by 2ohms of resistance (if my measurements were right).


So a few things:
Has anyone had any experience with changing this cable completely from the front to the back?
Was this (mine) an isolated incident?
Considering the age of these cars, their sensitivity to electrical fluctuations etc,,, is it a prudent MUST check at this point?
Are people finding there is a difference between what the alternator is putting out compared what is actually making it to the battery?

I dont know if a fire could have been caused by this problem,,, but it seems fragiliyt and electrical gremlins MUST be a possibility.

I would love to hear peoples thoughts, experiences and potential solutions to aging electrics in such a electrically sensitive machine,,,, the x100 XKR/XK8.

FROM THE 2003 M.Y. E.D.

 

Jay - What did you ever find out on this?

 

Hey Man... I check it fairly (fairly is generous if I'm honest) regularly. I haven't changed the cable out yet but what I did do was clean the hell out of it using a viniger and baking side solution, then, believe it or not a bunch of lemon juice. Got the copper to looking something like copper again and leaked some solder into the strands. Then, a thick shrink wrap. Temperature came down to normal/cool to the touch. I have two "new" cables, but have not installed them yet.

I also went around and cleaned up 12v main contacts, in the cabin on the RH side of the tunnel, at the false bulkhead, alt and starter (I don't know if I ever got to the starter) and the relay/fuse boxes under the hood and the ones in the door. All that was "good measure" stuff and honestly it didn't take long.

Hope that helps!? What are you seeing?
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Nothing like that, I hope - I haven't looked. I just found this thread as I was trying to find the wire gauge(s) that goes from the battery to the front and then from their down to the starter. I bought a beefier starter for my application and was curious how big the wiring was... and then I got curious on your situation...