Engine Bay (and other) Wiring Help?

[Rush]

I think I may have printed out his diagram; it didn't have any name on it. It was the only other one I could find for the 510 so I bet that's it. I should look to buy an actual copy of it. Dude put a lot of work into it & it does seem to be better than the Haynes one. I wonder if the one in the FSM is any better.

[yenpit]

The FSM diagrams are very difficult to read & I think broken up on different pages, making it even worse! Paolo marked all of his diagrams & I think marked as copyrighted too..........?? Regardless, as mentioned before, I bought his complete set, cuz I mess with so many 510's! Example..........if an owner has a 1971, then buy the 1971. He printed both MANUAL trans & AUTO trans. If the car was a 1971 AUTOMATIC, I suggest buying both the AUTO & the MANUAL trans diagrams, as there ARE differences. Having the AUTO diagram helps you understand some things! Of course, the biggest difference is the auto has a neutral safety switch down at the trans AND an additional relay up on the inner right fender..........these are illustrated in the AUTO diagram, not in the MANUAL diagram. One of my biggest beefs with all of the "aftermarket" diagrams like Haynes, is showing different color codes & NOT illustrating our USA emission wiring...........I want to see it all, correctly........no guessing!!

[Rush]

Agreed. I don't like the guessing game, either! I still have a couple of odd wires here & there that I need to sort out. I don't think my car was ever an automatic (at least not since 1989 when I bought it, anyway). I never even thought of that, but it's a good point!

[Rush1]

New name, new questions! Kinda.
I'm trying to sort out the wiring to the coil, distributor, etc.

Coming out of the saddle harness I've got
• Black/green that is spliced into black/blue.
• Black with white
• Black that ends in a female spade connector which has a black/red wire coming out with no end on it

My wiring diagram shows the black/red going to coil NEG and a relay. I don't see a relay within reach of that wire. I also don't see a carb switch or third switch (but I don't really know what those are). It shows black/white going to one side of the ballast and black/green coming out & going to coil POS.

I have the idea that all of that stuff was removed before I got the car & maybe that's why the black/green wire is spliced into the black/blue?

My distributor has only one spade terminal, not 2 as the diagram shows, too. It's a SSS distributor, I believe.

I know wires in photos are so hard to decipher but hopefully someone can make heads or tails of them.

Black/white on left side of ballast, black/blue on right. Black/green to coil NEG








This is the diagram:

[Rush]

Well, I think I've got everything right. I believe my ignition switch is shot, though. It works in all positions except start. When I put a meter on the black/yellow wire I get no reading when turning the key to the start position. I jumped a wire from the battery to the tang on the starter and it turned over so it's not the starter. I chased the B/Y wire and it's all good. When I stuck a tester wire in the plug at the ignition in the start position, I'm getting no reading on it when I turn the key.

Probably not the "right" way to try to isolate the issue but I believe I was able to isolate the problem. We'll see when the new switch arrives...

[Rush]

My cousin owns an auto electric shop (they rebuild starters, alternators, plow motors, etc). I just had him convert my standard, externally regulated alternator to self-exciting (internally regulated) one. So I'll be removing the stock voltage regulator from the car.

Based on the wiring diagram, do I simply solder the white/red, & the white/black wires together and do the same with the white & yellow wires? That's how it appears to me but I'd like to make sure.

Also, what happens to the white/blue wire that looks like it goes to the reverse switch(?)? Incidentally, I still haven't gotten my reverse lights working and so far, it's the only thing that doesn't work. I may have had the wires plugged into the wrong leads but I'm not sure yet; I had to solder connectors onto the switch and I figured I had a 50/50 shot at plugging the wires into them correctly. That whole reverse light program is a bit of a mystery to me for some reason.

[loungin112]

Based on the wiring diagram, do I simply solder the white/red, & the white/black wires together and do the same with the white & yellow wires? That's how it appears to me but I'd like to make sure.

That's what I did. No issues to date.

The blue wire....I think I remember there is power going through that wire. I think I just capped it off and wrapped it up good in electrical tape.
My reverse lights don't work either. But, I haven't checked the solenoid at the transmission and the rest of my wiring was crap from the PO, so I need to track it down still.

[Rush]

Thanks, Loungin! If I sort out the reverse light issue, I'll post it here. Maybe it'll help you, too.

That white/blue wire, I think is ignition "on". Maybe I can use it to trigger a relay to a buss bar.

[iceman510]

Great timing and related question happening here. On my '73, I have one red/black wire coming out of the harness near the wiper motor which I know is the one of the reverse light switch wires. I believe it is the wire that goes through the firewall to the rear harness and to the actual reverse lights in the rear combination lamps (have to verify with the ohmmeter yet). Should there be two red/black wires in this section of the harness in the engine compartment?

I have the same diagram you posted above, and it shows a green wire spliced with the red/black and white/blue just above the fuse box in the diagram. In actuality, the green and white/blue are joined at the same pin in the connector at the fuse block itself (4 terminal connector if I remember correctly, as I looked at it last night). I am trying to find where the power side of the red/black circuit that goes TO the reverse switch should come off the harness if it it truly spliced into those other two wires. Unfortunately I stupidly wrapped most of my harness before sorting out the reverse light circuit.

Rush, do you have two red/black wires from the harness to the reverse switch? Also, I don't think you need to do anything to the white/blue at the old voltage regulator connector except protect as mentioned. It is a 12V+ input from the fuse box to the regulator.

[Rush]

I do have 2 red/black wires running together there. Along with them are 2 blue/yellow wires (which, I think, went to a bunch of relays I don't have). I'm not sure how to test my reverse wires as I can't quite wrap my head around how they work for some reason (I've fixed every other circuit in the car so I'm not sure WHY this one is such a mystery! lol!). I have no power at either when I pop the tranny in reverse so I'm not sure if they, or one has power or if it's a dead end or what.

My harness is now a split loom so I might be able to fish around in there & see where it terminates for you (and me!). The hank of wires that go into the cabin, in the dash, are still stock wrapped but I should be able to get to anything if they're in the engine compartment.

I'll be putting my alternator back in today so I'll try to take a look.
That wiring diagram has totally been my BFF, though! I have a 15x24, color laminated version stuck at eye level on my garage door right in front of my car.

[Pjackb]

Mine doesn’t work either yet but it’s not surprising as there was some homemade wiring done by the PO
From what I understand from the diagram the white and blue wire from the regulator should connect with the red/ black wire before the backup switch, then a red/black wire should go all the way back to the lamp
This is not what I had done so I will have to redo it and see

[Rush]

I just installed my alternator & converted the wiring to internally regulated. I wasn’t able to chase the reverse wires back but I do now have power in one of them. I’ll need to jack the car up so I can fit my noggin underneath & hook up the wires. Maybe I’ll get it right this time! *blows on dice*

[iceman510]

Yes, one of the red/black wires should have power (the one that meets with the blue/white), the other red/black routes into the cabin, to the center of the dashboard and meets the chassis harness (I think a three pin connector in mostyears?) down the spine of the car back to the reverse lights, where it will ground after the bulb. The reverse switch merely completes the circuit to the reverse lights when closed. I think you're almost there!

[Rush]

Thanks! I'll keep this updated with what I find!

[iceman510]

Over the weekend I fixed my reverse light wiring issue. Looking at the diagram it show a green wire coming off the fuse box spliced to the white/blue wire to the voltage regulator and also one of the red/black wires to the reverse light circuit. I had only one red/black wire coming out of the harness at the location near the master cylinders.

First I tested continuity and verified the red/black there is the wire that goes into the dash harness then connects to the rear chassis harness and then back to the actual reverse lights in the rear combination lamps. This left me with needing to add the source branch of the red/black that will eventually connect to the reverse light switch in the transmission. I peeled back tape and was able to find the location of the original splice (deduced as such since there was not trace of wiring insulation left to verify the color, but location makes sense). I neglected to take a photo of the severed splice device, but the location was about 8" from the 6 pin connector that attaches to the fuse box.

As you will from the first photo, that actual splice of the blue/white to the green occurs in the connector terminal itself, at least in my car.

fusebox connector 2.jpg (527.47 KiB) Viewed 140 times

Tracing the green back about 8" from the 6-pin connector as mentioned, under some electrical tape I found the old splice. It was a small copper double crimp that had the joining wire cut off and the crimp remained only on the green wire. I spliced in a number of feet of red/black to reach the transmission, put heat shrink over the new splice and retaped the harness in the fuse box area. As soon as I power up the car I will verify this works, but I have no reason to think it won't.'

wire splice 2.jpg (512.64 KiB) Viewed 140 times