Wires in engine bay

[JnJJunk]

Hey guys working on my 1970 c10 and I have come across some stuff that I just cant quite pinpoint. I've looked on the wiring drawing and it is not really helping me out. Heres a couple pictures.

The first two are all on system. There is a red wire that runs into the fire wall, a blue and a black wire with a plug that was on top of the manifold, a green wire to the trans, and a green wire to the temp sensor on the passenger side of the block. Then there is a relay on the fire wall that all this comes out of. I thought this was the TCS system but I did not think that started until 71.

The last picture is of wires by the coil. The yellow one goes to the coil but the other two were just taped up in the harness.

<blockquote class="imgur-embed-pub" lang="en" data-id="a/xXn0V"><a href="//imgur.com/a/xXn0V">View post on imgur.com</a></blockquote><script async src="//s.imgur.com/min/embed.js" charset="utf-8"></script>

[JnJJunk]

Forget that link

http://jnjjunk.imgur.com/

[RPBurris]

Did you ever have the motor in it? The first photo looks like alternator wiring? Yellow wire looks like it would go to the starter solenoid. I think the wire with the black plastic cap would go to the brake warning light on the frame? Or it might even be the horn. You will probably get more replies. These trucks usually have pretty simple wiring but sometimes its best just start new. Shoddy wiring over 40+ years can give unexpected gremlins at any time.

[JnJJunk]

The motor was in it. Most of the wires were disconnected. The only ones that were connected was the green one to the temp sensor. The yellow one to the coil, and the green one to the transmission.

Someone replaced the stock generator with a self regulating one. So it was moved to the passenger side.

[JnJJunk]

This is the yellow wire that goes to the coil, the other two were just tied up into the harness.

This one and the last picture are all tied together. The relay and all. There is a red wire that goes through the fire wall into the fuse box

[JnJJunk]

Does any body know what that relay is in the second picture?

[QKENUF4U]

Originally Posted by JnJJunk

Does any body know what that relay is in the second picture?

the relay is the blower motor HIGH SPEED relay..... wiring is goofy on mine but has the same plugs .. the big plug on the two outside (as you have it) then i have a seperate RED that goes across into the cab and plugs into the RADIO fuse spade.. more that like wrong with that wire but it works so im leaving it alone... really not needed in my case anyways since my heater core is junk and i wont be driving the truck on crap days anyways...

[JnJJunk]

Originally Posted by QKENUF4U

the relay is the blower motor HIGH SPEED relay..... wiring is goofy on mine but has the same plugs .. the big plug on the two outside (as you have it) then i have a seperate RED that goes across into the cab and plugs into the RADIO fuse spade.. more that like wrong with that wire but it works so im leaving it alone... really not needed in my case anyways since my heater core is junk and i wont be driving the truck on crap days anyways...

I'm not sure how that could be the blower motor relay because all the wires stay out side of the cab except for the red one to the fuse box.

[El Dorado Jim]

those plugs in your hand look like they may plug onto an air conditioning compressor, i will take a look at my truck later and see if i can tell what you have

[JnJJunk]

Originally Posted by El Dorado Jim

those plugs in your hand look like they may plug onto an air conditioning compressor, i will take a look at my truck later and see if i can tell what you have

That would be great I still cant wrap my head around it, the only one that has a place to connect is the little round one. And that plugs into the trans.

[El Dorado Jim]

I checked my truck ,it is a 72, has wires similar to the ones in your pic with the relay, mine doesn't have a relay on the firewall like yours, those wires go to an ac compressor....sorry i cant help on the other wires...

[JnJJunk]

I'm going to give this another bump. I need to add better pictures!

[JnJJunk]

I spent some time reading on a chevelle website, I figured out that those wires are for the TCS system.