Big Short

[fab415]

I bought a 62 Continental a couple of months ago. The prior owner had installed an aftermarket ammeter under the dash. It was wired into the lower part of the power box, but not sure exactly how or where. Anyway, I decided to remove it today. I thought the battery was disconnected, but it wasn't. The positive wire grounded out to the body as I was pulling it out. Now when I turn the ignition on, nothing---I've lost all power. Stupid mistake I know. But any guidance on how to trouble shoot?

[Lee]

Could be anything, and this is only general advice, but the prior owner probably ran the main fuse box power in a loop from where the battery cable and generator output terminates at the solenoid, through the ammeter, and then back to the power box feed. So when it shorted, it melted that wire, and now no power to the fuse box. You’ll have to open the lower section of the power box and see exactly how it was wired. If you are lucky, only the add-on wiring for the ammeter is fried, and start by bypassing whatever was wired-in.

[papawayne]

It might have cooked the main ground that goes from the battery ground to the frame on the passenger side if the car. This is a place where this sort of thing happens, and it is not a bad fix. Look for a disconnected/burnt connector on the frame, and a hanging wire. Please note the word frame is used euphemistically. Perhaps you've already checked this. Wayne

[TonyC]

Right; these cars are unibody, even more unibody than cars made today. So basically, the whole thing is a frame.

But I concur with the others. Look down into the understructure in the engine bay, from the battery to the fuse box and all points between, for any cooked wiring. It could be a fusible link that got fried (they did have those back then), or some other wire in the general vicinity. But these electrical systems are actually quite resilient; the killing of one wire won't kill the entire car. Find and fix the short, and you should be good to go.

---Tony

[fab415]

the ammeter was wired to the starter relay.

[1Bad55Chevy]

It was wired like this?

ammeter-schematic.jpg (14.44 KiB) Viewed 220 times

Or like this?

images.png (13.44 KiB) Viewed 218 times

[1Bad55Chevy]

Right; these cars are unibody, even more unibody than cars made today. So basically, the whole thing is a frame.


---Tony

This statement hurts my brain...

[Lee]

If you return the heavy wire coming back from the voltage regulator to the battery side of the solenoid, it should be back to the way it was originally wired.

[fab415]

It seems to have been wired like the first diagram above. One wire was connected to the left side of the starter relay and the other was connected to all these wires in the photo (with the bolt). Should these wires be connected to the right side of the starter relay?

I do not see any fried wired anywhere. The grounds are all good. Could it have fried the starter relay?

[Lee]

It seems to have been wired like the first diagram above. One wire was connected to the left side of the starter relay and the other was connected to all these wires in the photo (with the bolt). Should these wires be connected to the right side of the starter relay?

I do not see any fried wired anywhere. The grounds are all good. Could it have fried the starter relay?

Yes, to your first question (the battery side of the solenoid to eliminate L/R confusion). When you get those back, you should have all accessories, etc operational.

It’s possible the ammeter loop had a fuse, or fusible link somewhere in it, and that’s why you don’t see fried wiring.

The starter relay should be fine.

[TonyC]

Right; these cars are unibody, even more unibody than cars made today. So basically, the whole thing is a frame.


---Tony

This statement hurts my brain...

Sorry about that, not intended.

Back to OP, you do have a shop manual for your year, right? The starter schematics are in there. It will take a bit of time to study them; but once you do, you'll know exactly how things are supposed to be wired and be able to fix whatever may not be right.

---Tony

[fab415]

PROBLEM SOLVED!!

I connected those wires to the battery side of the starter relay, and everything works now!

Thanks very much for the help!

[TonyC]

O, good ! Simple solutions to complex problems are cool. Glad you're good to go now.

---Tony

[fab415]

Yes, glad it was an easy fix. Thanks again.

[papawayne]

You can feel really tall, now that your short is fixed! Good luck, but great thinking. Wayne