Below should be a thumbnail of a section of a wiring diagram from a 68 Chevelle (external mechanical voltage regulator and 2-wire delco alternator. I am trouble-shooting problems and before I take out the cluster, I was thinking I might be able to access this splice from under the dash, if I knew where it is.

Anyone know if this pink-wire splice is near the fusebox or accessible without pulling the gauge cluster? There's about 6-8 inches of taped wire bundle I can get to, but I don't want to tear off the tape if the splice is up higher and out of reach.

This picture shows the interior side of the bulkhead connector. The red circle indicates a splice. The 12g pink wire from the bulkhead splits into two 12g pink wires. One goes to the back of the fusebox (very close), the other goes to the ignition switch. Thanks.

Just guessing but it's fairly easy to pull the fuse box and check on the back of it.

Just guessing but it's fairly easy to pull the fuse box and check on the back of it.The fuse box is all apart Dean. The 12g wires from the fusebox AND from the bulkhead go inside a thick taped bundle.

It seems logical it is close to the fusebox, much like the red wires power feed splice by the horn relay.

That may very likely be where it's located then.
Maybe someone that knows for sure will reply in a day or two.

That may very likely be where it's located then.
Maybe someone that knows for sure will reply in a day or two.It'll be all torn apart by tomorrow if someone doesn't know tonight. :D

If you are looking for the splice by the horn relay, it should be by the Ext. Voltage regulator if you have one. My splice on my 69 is right by the voltage regulator on the drivers side right by the front head lights. Check out this diagram, thats why it is best to stay OEM so people can read the diagrams for these cars and find stuff when you have to trouble shoot problems. The splice maybe wrapped in black electrical tape, mine was. It was right by the horn relay between the voltage regulator and the radiator. The splice under the dash might be wrapped in electrical tape as well. I would just go slow when unraveling and look for 4 wires usually redish maybe pink, 12 gauge. one will come out the firewall to the splice, one from the healight switch to the splice, one from the ignition switch to the splice and one to the fuse box. This is were you get your juice from .

Check this out Bro::thumbsup:
http://www.madelectrical.com/electricaltech/chevymain1.shtml (http://www.madelectrical.com/electricaltech/chevymain1.shtml)

Also what problems are you having?

If you are looking for the splice by the horn relay, it should be by the Ext. Voltage regulator if you have one. My splice on my 69 is right by the voltage regulator on the drivers side right by the front head lights. Check out this diagram, thats why it is best to stay OEM so people can read the diagrams for these cars and find stuff when you have to trouble shoot problems. The splice maybe wrapped in black electrical tape, mine was. It was right by the horn relay between the voltage regulator and the radiator.

Check this out Bro::thumbsup:
http://www.madelectrical.com/electricaltech/chevymain1.shtml (http://www.madelectrical.com/electricaltech/chevymain1.shtml)Hi shonuff and welcome to the forums. Actually, I'm looking for a splice located near the fusebox inside the car. It would be pink wires, not red ones like at the horn relay. My problem right NOW is I don't want to remove the dash bezel and gauge cluster if I don't have to.

The splice under the dash might be wrapped in electrical tape as well. I would just go slow when unraveling and look for 4 wires usually redish maybe pink, 12 gauge. one will come out the firewall to the splice, one from the healight switch to the splice, one from the ignition switch to the splice and one to the fuse box. This is were you get your juice from .


Read this part.

The splice under the dash might be wrapped in electrical tape as well. I would just go slow when unraveling and look for 4 wires usually redish maybe pink, 12 gauge. one will come out the firewall to the splice, one from the healight switch to the splice, one from the ignition switch to the splice and one to the fuse box. This is were you get your juice from .


Read this part.
this part

Pete, Hope I'm not too late.:(
The 12ga pink/black wire from the buss bar on the fusebox and the 12ga pink wire from terminal location B-X on the bulkhead connector are spliced together with the pink wire from the ignition switch about 12" from the fuse box.
There is another splice on the 12ga red wires from the fusebox buss bar and 12ga red from terminal location D-V on the b/h connector to the 12ga red wire from the headlight switch connector and the 12ga red wire from the ignition switch in about the same location.

The 20ga pink wire coming from the GAUGE fuse goes is spliced into 5 other 20ga pink wires further up the harness to supply 12v to the gauges or idiot lights.

There is another splice of four 20ga white wires, about 12" down from the headlight switch that connects the dome light/courtesy light grounds together so they turn on with the headlight switch.
See the pics, I'll email full size ones to you, hope that helped.
BillL

Good info, I hope he didn't tear it up yet....Then he will have more problems. Thats the problem sometimes, your lookn for one problem then dominoe to other problems trying to find one problem. Now you got to fix multiple issues instead of one. Been there done that......LOL :beers:

Quick question (then long response):
I have a triple-gauge set under the dash with mechanical oil pressure and water temp. The OLD water temperature wire is wrapped up and taped to the wire bundle inside the engine compartment (I believe this is correct). Where should the old (dark blue) OIL light wire be terminated? It should run directly from the OIL light through the bulkhead to the the oil-sender gauge if the idiot lights were working. I'm thinking the OIL light and TEMP light are completely disconnected and won't light up at any KOEO position. Please tell me if this is correct.Pete, Hope I'm not too late.:(
The 12ga pink/black wire from the buss bar on the fusebox and the 12ga pink wire from terminal location B-X on the bulkhead connector are spliced together with the pink wire from the ignition switch about 12" from the fuse box.
There is another splice on the 12ga red wires from the fusebox buss bar and 12ga red from terminal location D-V on the b/h connector to the 12ga red wire from the headlight switch connector and the 12ga red wire from the ignition switch in about the same location.

The 20ga pink wire coming from the GAUGE fuse goes is spliced into 5 other 20ga pink wires further up the harness to supply 12v to the gauges or idiot lights.

There is another splice of four 20ga white wires, about 12" down from the headlight switch that connects the dome light/courtesy light grounds together so they turn on with the headlight switch.
See the pics, I'll email full size ones to you, hope that helped.
BillLBill the info you sent helped a lot! I was able to check the Pink wire splices from under the dash without removing the cluster, and the red wire splice is only an inch or two past that point in the wire bundle. But these splices were good. I've since pulled out the gauge cluster far enough to look for the 20g pink 5-wire splice but haven't done it yet. I did notice that one white wire was left hanging and cut and the courtesy light wires are "new" running from the DS to the PS.

Man this has been a lot of work! But in the end I'll have fully documented the wire color changes and replaced a lot of wires :D . I haven't tested the brown 24-g bypass wire resistance between the fuse and the ignition switch yet. But all indications are that it is intact. Isn't is nearly impossible to disconnect wires from the bulkhead? I can see why they get $400 for these wire bundles.

One clue I'm chasing is that lights of the triple-gauge set I have under the dash used to dim with the gauges in the dash. This should NOT happen!! The triple-gauge lights were spliced into the power wire (not the light wire) of the tach. This was fed from the fuse box at the "CLOCK" fuse. So they (and the tach) must have been grounding through the headlight switch somehow. This may explain why I could zero my tach with the headlight switch when it was reconnected a few weeks ago :sad:. Once I've fixed this, I'm going to set up a few extra ground wires for the cluster and headlight switch. Then hook up the battery and test things. I have a carpet burn on my shoulder!

My 66 had a 4 way splice or two in the wiring from the key switch to the fuse box. One was the pink wire, IIRC. I had to take it apart because the insulation had melted off of the pink wire in most places, and had helped fuse the other wires together. Car ran ok in spite of all this.

I ended up unwrapping the entire harness bundle and the pink wire splice was near the middle of the run. It would have been near impossible to access with the steering column and dash in place, I think. I did not discover most of the melting until the dash, and the cluster were out. Took the dash out to fix the dash lights, and found a host of other issues. Easiest dash I have ever removed. Put it back in and, in spite of my best efforts, it works!

WAY TO GO Bill :hurray: :thumbsup:

Okay, bad news first: I tore all the tape off all the wires after removing the bezel and gauges. I made a small crack in my A/C-style glove box liner when removing it. I don't know if any of this is actually going to fix the problems I've been having. :(

Good news: I recovered five bulbs from inside the gauge cluster from when I last had the gauges out. I didn't drop a single bulb inside this time. All my wiring, every circuit, is annotated now. I've repaired all poor splices with solder. The gas gauge light intermittent problem is fixed. I can rebuild the circuits that are missing or re-engineered (for example the courtesy lights and associated white wires). The triple gauge cluster will have a properly dimmed circuit linked to the cluster lighting. The tach will be rewired with correct colors and not influenced by the headlight switch variable resistor. I found what appears to be a couple mistakes in the 68 wiring diagram. (For example, does the turn blinker terminal use an orange and a white wire?) I can incorporate all the wires into single bundles rather than two bundles running next to each other. The economy will benefit from my purchase of new colored wires and wiring tape at NAPA. :yes:

Also, this will be a good time to replace the carpet and finish "chroming" the dash bezel. Yes. BillL you are the man. :beers:

"I'm thinking the OIL light and TEMP light are completely disconnected and won't light up at any KOEO position. Please tell me if this is correct."

Yep, it is.:yes:
Oil pressure light socket is a dual terminal bulb socket with a pink (12v from GAUGES fuse and the 5-wire splice) and dark blue wire. The dark blue wire goes through the bulkhead at position B-Z, then to the oil pressure switch on the motor by the oil filter. When there's no oil pressure, the wire is grounded, and turns on the light. When oil pressure builds, the switch is opened, the light goes off. If you want to keep the light, it's not a big deal to get a tee fitting and connect the switch and the oil line to the gauge at the tee.

Temp light is a dual terminal bulb socket with the same 12v feed from the pink wire, and a dark green wire. I think the next two sentences are correct, but I may be wrong.

The dark green wire is grounded with KEY ON ENGINE OFF through the ignition switch. When the key is turned to the START position, the ground is broken in the switch and the light goes off.

OK, the dark green wire goes from the ignition switch, through position C-T of the bulkhead connector to the temp sender in the left cylinder head. This sender has an open circuit until the engine temp reaches around 240~260degrees, then it closes, grounds to the engine and the light comes on.

I'm not sure what a "turn blinker terminal" is. The 2-wire terminal I think you're talking about is for the brake light switch, orange and white wires in a terminal with locking ears, see pic.

There is a typo in the diagram, good catch, Pete. The wire listed as "14 DR" from the fusebox to the brake light switch should be "14 OR". The wire on the other side of the switch going to the turn signal connector should be "14 WH".
The 14 PPL wire from the DIR. SIG flasher connector isn't identified either.

This has been interesting and informative for me, also. Glad to help, happy to learn.:thumbsup:
BillL

If you want to keep the light, it's not a big deal to get a tee fitting and connect the switch and the oil line to the gauge at the tee.Cool, I'll try and find this. I want this.
I'm not sure what a "turn blinker terminal" is. The 2-wire terminal I think you're talking about is for the brake light switch, orange and white wires in a terminal with locking ears, see pic.Yep that was it. it was late and my brain wasn't working well.
There is a typo in the diagram, good catch, Pete. The wire listed as "14 DR" from the fusebox to the brake light switch should be "14 OR". The wire on the other side of the switch going to the turn signal connector should be "14 WH". The 14 PPL wire from the DIR. SIG flasher connector isn't identified either.

This has been interesting and informative for me, also. Glad to help, happy to learn.:thumbsup:
BillL Well, I have a couple other differences in the wiring diagram I want to run past you Bill.


In the diagram, the backup lamp switch, regardless of the location (column, Muncie, etc) shows it is fed by a 20g pink wire directly from the fuse box. This 20g pink wire is joined at the fuse box by a 12g pink wire that runs directly to the direction signal flasher.

Instead, there is only a 12g pink wire running from the fuse box to the direction signal flasher, and the 12g wire is spliced into the 20g wire at the direction signal flasher connector. Correct? (This will work fine as far as I can see)


My headlight switch connector has two brown wires spliced together into the bottom rear-most (relative to the car) connector. The numbers on headlight switch suggest this connects to terminal “3”. The diagram suggest there should be one wire at “3” and another brown wire connected immediately forward (at position “4”) Either setup will also work fine as far as I can see because the 3-4 terminals are connected together on the switch.
The Backup light switch lists an 18g dark green and 18g light green wire running from the switch through the firewall, to a connector inside the dash. The pink (see item 1 above) and light green wire exit the other end of the connector.

My dark green and light green wires are HUGE! They must be at least 12g, probably 10g. They are connected together continuously like lamp cord. Is this similar to yours, or is this part of the previous owner’s hack-job?


Inside the engine compartment, the wire from the bulkhead to the positive terminal of the coil is listed as “20 W/OR/PPL”.

What color is this wire really? Mine is currently 12g black but this was the wire you and Mike B. replaced at Chevellabration in the parking lot (which I appreciate tremendously to this day!)



Thanks again. The rest of the wiring corrections deal with convertible specific issues (courtesy lights) and the light-blue/darkblue wire connections on the wiper and washer.

Also, there is a GREY wire running from the fusebox to the GREY splice. The wiring diagram has this labeled as "G" which would be green. It is definitely GREY on my vehicle.

Also, there is a GREY wire running from the fusebox to the GREY splice. The wiring diagram has this labeled as "G" which would be green. It is definitely GREY on my vehicle.
Yep, someone forgot to add the "Y". Dang, Pete, you've really been studying this!:cool:
BillL

Yep, someone forgot to add the "Y". Dang, Pete, you've really been studying this!:cool:
BillLThey forgot it about three times. This is the way my brain works... learn it or don't. There's not much in between. Made grad school a PITA. :yes:

Planned and drew all the new/repaired circuits, and bought all the new wires today. The previous owner wrapped the wires together well, but there wasn't a trace of solder or crimping on any non-OEM splice. The main Red power wires in the front of the car (along the radiator support) were 10g on the outsides, but only 12g under the tape. All the wires except the headlight wires had at least two non-soldered splices. Fortunately the only OEM splice I need to re-do anywhere is the three 10g Red wires located next to the horn relay. I plan to solder them, install a crimp, then heat the crimp to remelt the solder. Some heat shrink to make it look good too.

Who sells the best wire-loom wrapping tape? I liked the way the GM guys made knots around the places where wire bundles exited the main loom. It would be hard to do that with sticky tape.

Cool, I'll try and find this. I want this.

In the diagram, the backup lamp switch, regardless of the location (column, Muncie, etc) shows it is fed by a 20g pink wire directly from the fuse box. This 20g pink wire is joined at the fuse box by a 12g pink wire that runs directly to the direction signal flasher.

Instead, there is only a 12g pink wire running from the fuse box to the direction signal flasher, and the 12g wire is spliced into the 20g wire at the direction signal flasher connector. Correct? (This will work fine as far as I can see)

Yep, the two are connected at the flasher.

My headlight switch connector has two brown wires spliced together into the bottom rear-most (relative to the car) connector. The numbers on headlight switch suggest this connects to terminal “3”. The diagram suggest there should be one wire at “3” and another brown wire connected immediately forward (at position “4”) Either setup will also work fine as far as I can see because the 3-4 terminals are connected together on the switch.
Two brown wires are connected at the switch on the same terminal as you said. The diagram isn't correct. These are the wires for the front parking lights and taillights.


The Backup light switch lists an 18g dark green and 18g light green wire running from the switch through the firewall, to a connector inside the dash. The pink (see item 1 above) and light green wire exit the other end of the connector.

My dark green and light green wires are HUGE! They must be at least 12g, probably 10g. They are connected together continuously like lamp cord. Is this similar to yours, or is this part of the previous owner’s hack-job?

I can't help you out there, yet. My car and the harness I have are from an automatic trans car, and doesn't have the dark green/light green wires. The wires may be molded together for ease of assembly, and may have thick insulation over a thin wire because they're outside the car and close to the exhaust.

Inside the engine compartment, the wire from the bulkhead to the positive terminal of the coil is listed as “20 W/OR/PPL”.

What color is this wire really? Mine is currently 12g black but this was the wire you and Mike B. replaced at Chevellabration in the parking lot (which I appreciate tremendously to this day!)

IIRC, the fabric insulation cover is white with orange or red "dashes" more than a solid stripe. I'd have to unwrap my harness to tell you for sure, and I ain't gonna. Didn't you keep your old one, or did Mike throw it as far as he could??:p



Hopefully this thread will help some other folks.
BillL

I hope it helps someone else too. It's sure helping me. Sorry about all the questions but I only have the electrical diagrams to work from, and it's hard to say what was changed and what's original. If I'm going to do this, I want it to be correct or better.:thumbsup:

I found a very nice connector for the 10g Red wires, and have started reassembly of the front engine harness. I'll post some pictures as this goes along. Still wondering who sells the best wrapping tape.

I don't know what happened to the old wire Mike took out. I blocked as much of that stuff from my mind as I could.

Still wondering who sells the best wrapping tape.

Check your email.
BillL