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So just sent all day fixing a no start. Ended up being an open in BAT+ wire to the COPs, so I had no primary voltage. Now the car starts but when I went to grab my test light it shocked the hell out me. Light was hooked to ground, and I soon realized if I touched a ground I got shocked. Anyone have any idea where I should start, seems like a bad ground but I have no idea where to start on this one.
Test light connected to battery ground other end in my hand when I went to pick it up, and the car was off. There's a constant voltage going through the ground that shocked me until I dropped the test light. It's a 2004 mercury grand marquis 4.6. After that when I touched any ground I noticed I was getting shocked with the car off. After about 5min with car off it seemed the voltage disapppates and you don't get shocked.
It's not that important they only called me in to fix the no start, as they started throwing parts at it and nothing was working cuz BAT+ to the COPs was open and no part is going to fix a broken wire. And they would have put a Computer in it if it didn't require new keys to do that, so they called me to confirm ECU. Man they wasted a lot of money before calling me maybe they call me quicker next time . But anyways they might not call me back to fix this shocking problem but I've never seen it before and have no idea what could be possible cause; ac voltage, bad grounds, short to BAT+....
The car wasn't even running?!?
Hid headlights?
I've worked on a lot of those cars, I sure would like to know what was going on. If you get called back to look at it, make sure to keep us in the loop.
I'm with Noah on either HID headlights, or, all of the coils are partially shorted - that's about all I can come up with there ... aside from a household power wire laying on the roof or something.
Ahh I should read the posts before posting ...
Anyway, there could be something strange going on where all the coils are firing like crazy with the key on, engine off. Eric O. of South Main Auto has a video of something similar from a while back that I recall seeing. He wasn't getting zapped through ground, though.
Last edit: 6 years 3 months ago by Smitty Smithsonite. Reason: I am brain dead ...
Smitty Smithsonite wrote: I'm with Noah on either HID headlights, or, all of the coils are partially shorted - that's about all I can come up with there ... aside from a household power wire laying on the roof or something.
Why not use a volt/ohm meter or better yet scope to figure exactly how much and what type of voltage there is and where is it ( batt vs engine block etc)? Might get you going the the right direction anyway. Plus you can the measurement and see if anything changes
Just throwing this out with my limited experience and 0 knowledge on this car. Maybe pull the RAP relay right after shutting down car and see it still has the same problem. If not, maybe a bad ground on one of the accessories the RAP keeps alive or bad ground in RAP circuit itself?
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