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Help determining 2 wires

pearljam724

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69 Coronet - Anyone know what these 2 wires are for ? One is yellow, other dark green. Original air conditioning car, but not hooked up, They run along the fire wall and end behind the distributor. I don’t think they were attached to anything when I bought the car.

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The dark green looks like it is just a short wire that is bolted to the firewall? It appears to be a ground...

Any chance the yellow is actually gray but looks yellow because of residue? If so it could be the oil pressure sender wire
 
I think you’re definitely right about the yellow being oil pressure sender. It has aftermarket gauges. So that explains one. I’m pretty sure it’s yellow. But, it’s discolored and old. So it may have turned yellow perhaps.
I wish I had a good colored schematic. The one in the manual stinks being it’s black and white. I have a convertible and for the life of me, I can’t get the rear courtesy lights to work. I’ve had the panels off, changed and fiddled around with bulb sockets. They are clean. To no avail. I wonder what the green wire is supposed to ground, as you say. Thank you, greatly
 
I think you’re definitely right about the yellow being oil pressure sender. It has aftermarket gauges. So that explains one. I’m pretty sure it’s yellow. But, it’s discolored and old. So it may have turned yellow perhaps.
I wish I had a good colored schematic. The one in the manual stinks being it’s black and white. I have a convertible and for the life of me, I can’t get the rear courtesy lights to work. I’ve had the panels off, changed and fiddled around with bulb sockets. They are clean. To no avail. I wonder what the green wire is supposed to ground, as you say. Thank you, greatly


What bulbs are you using in the courtesy lights? They take an odd bulb with both terminals on the bottom, the brass base doesn't serve an electrical function at all.... May times someone puts a more conventional bulb in those sockets with acts as either an open or a dead short depending on how lucky you are...
 
What bulbs are you using in the courtesy lights? They take an odd bulb with both terminals on the bottom, the brass base doesn't serve an electrical function at all.... May times someone puts a more conventional bulb in those sockets with acts as either an open or a dead short depending on how lucky you are...
I ll have to check bulb number. It matched end wise.
 
Yellow is for the oil pressure switch; dark green apparently goes to the alternator:
http://www.mymopar.com/downloads/1969/69CoronetB.JPG
I thought it was alternator, must go to the original gauge. Those must be the two wires someone disconnected when installing aftermarket gauges. Now that I have a better speedometer and everything works on it. I can see if that gauge works too. I prefer aftermarket gauges. But, it’s nice to know what works and what doesn’t. Thank you, you guys are a good bunch on here
 
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If that green wire is bolted to the firewall like it looks like in your photo it has nothing to do with the alternator or gauges.....

The only green wire that typically goes to the alternator is on a 70 or newer vehicle....
 
If that green wire is bolted to the firewall like it looks like in your photo it has nothing to do with the alternator or gauges.....

The only green wire that typically goes to the alternator is on a 70 or newer vehicle....
It’s not bolted to the firewall, both wires are bundled in with some other stuff on the firewall just hanging there loose. I pulled them out for a better pic. I think it is alternator. Explains exactly why those two are unconnected, aftermarket gauges. I’ll run a jumper wire in next few days to check it. I don’t think it was ever bolted to firewall. Someone hacked all of the wiring to alternator to hook up new gauges. But, I know. Eye hole connector makes that theory confusing. You may be right.
 
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If that green wire is bolted to the firewall like it looks like in your photo it has nothing to do with the alternator or gauges.....

The only green wire that typically goes to the alternator is on a 70 or newer vehicle....
I offered the link to the actual original wiring diagram to his specific car that shows otherwise.
Of course, who knows what changes in the wiring have occurred over the last 50 years, but according to the diagram, there is indeed a green wire going to the alternator.
 
[QUOTE="I wish I had a good colored schematic. The one in the manual stinks being it’s black and white. I have a convertible and for the life of me, I can’t get the rear courtesy lights to work. I’ve had the panels off, changed and fiddled around with bulb sockets. They are clean. To no avail. I wonder what the green wire is supposed to ground, as you say. Thank you, greatly[/QUOTE]
I finally just bought a good set of colored pencils (they were only about $5 from Amazon) and went to work on my FSM when I was troubleshooting my wiring.
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I offered the link to the actual original wiring diagram to his specific car that shows otherwise.
Of course, who knows what changes in the wiring have occurred over the last 50 years, but according to the diagram, there is indeed a green wire going to the alternator.

Sorry I didn’t see the link, you are 100% correct. In my experience that wire is generally dark blue.. Whatever I agree it’s actually probably the voltage regulator connection going to the alternator
 
Is the voltage regulator only needed when using the original gauge ? I ll have to take a look at how mine is wired. There’s a new one on the firewall, so this kind of adds to the confusion that it’s not hooked up. It’s definitely a alternator wire. Same exact dark green and gauge thickness.
 
Do you have access to a basic meter? I would ohm the wire, check for continuity to the green wire at the alternator & wires at the voltage regulator...

Take a picture of your regulator & post it
 
Is the voltage regulator only needed when using the original gauge ? I ll have to take a look at how mine is wired. There’s a new one on the firewall, so this kind of adds to the confusion that it’s not hooked up. It’s definitely a alternator wire. Same exact dark green and gauge thickness.
The purpose of the voltage regulator has nothing to do with a gauge; it is a literal name - voltage regulator.
It controls alternator output voltage.
 
Welp, we were all wrong and it almost cost me an engine rebuild and hearing in my left ear, lol !
Trying to make this short as I can. I’ve done a ton of crap to this car in this past few weeks. Distributor leak fix, new timing chain, u-joints, rear end leak, intake gaskets, fixed a couple major leaks and other things.
I had everything buttoned up and put back together. Cranked it, no fire. Cranked it 3 or 4 more times, no fire. I check for spark nothing. It was then I realized, that the green wire goes to the ballast resister and I forgot to put it on the coil. Praying, I hadn’t screwed up the timing gears when I installed them. Attach green wire, crank it for several seconds. Then the loudest backfire known to man. It literally sounded like a bomb went off in my left ear because I had the window down in my garage.
Thinking no way in hell did my pistons survive that. I put a screwdriver in each plug hole to test for holes. To my surprise they seemed ok. But, the next test was to crank the motor again to see if I damaged anything. I was scared that it would happen again. I’m telling you guys, had the hood been closed, it would have blown off. I think I had the distributor 180 out too. After I timed it 10 degrees in advance, it fired up first crank and idled good as ever. I previously timed it at top dead center on exhaust stroke. It amazed me that a piston didn’t blow a hole. Unbelievable, loud. No kidding, my left ear hurt for 3 or 4 hours and still does a little. I’ve witnessed a lot of backfires in my life. Nothing like this one. It wasn’t a pop or a loud crack. It was a bomb sound. Major percussion.
 
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That is some funny ****. The backfire was probably raw fuel igniting in the exhaust system.
I knew this one guy years ago....The type of guy that was fun to hang out with but was always doing stupid ****. One time he rented a big U-Haul truck when he moved from Reno to Sacramento. He liked to floor the gas pedal and turn the ignition key OFF for a few seconds, then turn it back on. It made some obnoxiously L O U D backfires....THEN blew the muffler wide open. He coasted it into the rental lot and turned in the keys quickly...
 
That is some funny ****. The backfire was probably raw fuel igniting in the exhaust system.
I knew this one guy years ago....The type of guy that was fun to hang out with but was always doing stupid ****. One time he rented a big U-Haul truck when he moved from Reno to Sacramento. He liked to floor the gas pedal and turn the ignition key OFF for a few seconds, then turn it back on. It made some obnoxiously L O U D backfires....THEN blew the muffler wide open. He coasted it into the rental lot and turned in the keys quickly...
That’s why I would never go into the renting business of any kind. Yep, that’s what happened to me. Raw fuel that was finally ignited when I eventually connected the green wire. No kidding, it’s been about 20 hrs and my left ear still hurts.
 
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