Modern electronics = Full rewire

-
J

JoeWillie

Member
Joined
Sep 13, 2023
Messages
12
Reaction score
8
Location
Greenville, SC
Well I purchased my 1973 Scamp a year ago. Have a 1969 Cougar from Jersey that I purchased 18 years ago when I was 24 and didn't know anything about cars, aka bought a rust bucket that fell apart within months. It is still in pieces, kids and a Navy career killed reviving it. Finally scraped up enough money to buy a drivable car and went looking for another Cougar and ran across the Scamp. I love it. Looks awesome and drove like a dream. It isn't a speed demon but is a ton of fun to just cruise around in. I inspected the hell out of it for rust but didn't spend enough time going through the wiring. Got up last week and the battery was dead. Figured the door got left cracked open. Put in a fresh battery, walked around to the drivers seat and all the magic smoke was escaping. Several expletives later the battery was removed and the smoke cleared. Went hunting for the short and found when I unplugged the modern stereo someone had buchered the car to install the short cleared. Started taking things aparts and on top of my fire there seems there was previous wire fire that was not properly repaired. The main amp meter cable from the battery had exposed wire along its whole length, a wiper wire had no insulation left at all under the wrap but still worked. The wires in the main harness are basically one piece. So here I am becoming a Scamp wiring expert. I have drawn up a new wiring schematic in CAD but had some things I have not been able to figure out. The only things being reused are the rear harness, the interior lighting circuit, and the A/C circuit. I am going to have to fix the A/C circuit. At some point in the past something stoped working right and they wired an extra switch to turn it on but otherwise controls work and it is ice cold. I have several plugs that were already disconnected that I am figuring out what they are.

Things I have not found or have not figured out:

Radio connection - why is there a wire from the Neutral Start/Backup Lamp circuit running to it?

The accessory lamps and time delay connector - can't find it

I have put a PDF of my CAD if anyone cares to look and comment.

Going to keep working on removing the old wiring, taking awhile labeling everything as I go and figuring out what everything is and how it works. Thanks ahead of time for any advise.
 

Attachments

  • Plan-Layout1.pdf
    108.6 KB · Views: 149
Oh yeah. Some other goals:

Figure out how to replace the instrument lamps with LEDs.

Replace the amp meter with a volt meter.

Go ahead and remove and repair/repaint the dash....I mean everything is out of it at this point.

Fix the hack job they did on the radio area of the dash and replace the bezel, also cut up to fit the new radio, probably going to need to find a replacement. Put a period look alike with bluetooth in it.
 
There's an old thread on here that has lots of good ideas for ammeter/ voltmenter. Also read the MAD ammeter article, and don't necessarily "do it their way"

www.forabodiesonly.com

Ammeter to Voltmeter...who does it?

Im interested in converting my stock ammeter to a voltmeter and was wondering which companies can do this, and approx how much they charged? I did a search and saw that redline does it for about 140, but I'm trying to see if anyone has any experience with other vendors? I thought about...
www.forabodiesonly.com www.forabodiesonly.com

 
If you want to pull the dash WITHOUT pulling the windshield, you will have to remove enough "stuff" (I don't know if the heater needs to come out) so that you can get up in there and cut the screws and nut clips with a die grinder. Then when you put it back in, you can get new nut clips and reverse them, so that you can put the screws back in from below
 
JoeWillie said:
that were already disconnected that I am figuring out what they are.

Things I have not found or have not figured out:

Radio connection - why is there a wire from the Neutral Start/Backup Lamp circuit running to it?

The accessory lamps and time delay connector - can't find it

I have put a PDF of my CAD if anyone cares to look and comment.

Going to keep working on removing the old wiring, taking awhile labeling everything as I go and figuring out what everything is and how it works. Thanks ahead of time for any advise.
Click to expand...
Do you have a FACTORY service manual? If not run over to MyMopar.com and download it, two volumes, one for chassis and one for body. Some of us here is whey it got posted

The radio connector is simply used as a junction point, the red is key switched accessary power to the radio, and the white is a branch to feed whatever is on the white line

If you go to about page 8-153 in the manual, the index says "radio" at D38. That is the coordinates on the schematic. So go down a few pages to 8-163, you see the radio, and the red wire to CI-13, the radio connection. Follow that wire down, B1-18W which means circuit B1, no. 18 ga. wire, and White.

Follow it painfully page by page back to the bottom of page 8-160 and you'll see it goes to connector CE-2B (engine bay) and AGAIN branches to wire D1-18BK. Follow that up to the top of page 8-158 and it goes to the turn flasher, connector CI-12. Now if you go forward some pages you'll find the engine bay connectors, that CE-2B above you'll find on 8-164 and is the big bulkhead connector

In the manual, go to about page 8-168. That chart is the "CI" Instrument panel Connectors. At the bottom left of the page is CI-8 the time delay connector. Notice it gives you an approximate location.
 
Relays. I would not fiddle with all the wiper relays. So far as headlights, make sure you make that circuit RELIABLE. You don't want to lose lights at 70+ at night.

I WOULD ADD a relay fired by the key "run" circuit, as voltage drop in that circuit is a big problem, and affects the voltage regulator, causing it to overcharge.
 
67Dart273 said:
Do you have a FACTORY service manual? If not run over to MyMopar.com and download it, two volumes, one for chassis and one for body. Some of us here is whey it got posted

The radio connector is simply used as a junction point, the red is key switched accessary power to the radio, and the white is a branch to feed whatever is on the white line

If you go to about page 8-153 in the manual, the index says "radio" at D38. That is the coordinates on the schematic. So go down a few pages to 8-163, you see the radio, and the red wire to CI-13, the radio connection. Follow that wire down, B1-18W which means circuit B1, no. 18 ga. wire, and White.

Follow it painfully page by page back to the bottom of page 8-160 and you'll see it goes to connector CE-2B (engine bay) and AGAIN branches to wire D1-18BK. Follow that up to the top of page 8-158 and it goes to the turn flasher, connector CI-12. Now if you go forward some pages you'll find the engine bay connectors, that CE-2B above you'll find on 8-164 and is the big bulkhead connector

In the manual, go to about page 8-168. That chart is the "CI" Instrument panel Connectors. At the bottom left of the page is CI-8 the time delay connector. Notice it gives you an approximate location.
Click to expand...
I downloaded the 1972 manual from MyMopar since they don't have a 73. That is what I have been using. I opened the two page electrical in MS Paint and as I add a circuit in my drawing I erase it in the book print. I have been using the pages you mentioned. They have helped alot in better understanding the prints.

I kind of figured about the junction but wanted to verify. Lots of that going on. Feels sloppy to me. I like dedicated circuits.
 
Last edited:
67Dart273 said:
Relays. I would not fiddle with all the wiper relays. So far as headlights, make sure you make that circuit RELIABLE. You don't want to lose lights at 70+ at night.

I WOULD ADD a relay fired by the key "run" circuit, as voltage drop in that circuit is a big problem, and affects the voltage regulator, causing it to overcharge.
Click to expand...
I mainly did the wiper because the dk green going to F2 had ZERO insulation from the firewall through to the dash switch. I am guessing the remains of the insulation are what have cemented the other wires into one piece.

The middle red wire in the ignition switch going to the main splice area and on to the firewall in one direction and fuse box in the other isn't completely bare but has several bare spots. Even burned through the wrap.
 
JoeWillie said:
I downloaded the 1972 manual from MyMopar since they don't have a 73. That is what I have been using. I opened the two page electrical in MS Paint and as I add a circuit in my drawing I erase it in the book print. I have been using the pages you mentioned. They have helped alot in better understanding the prints.

I kind of figured about the junction but wanted to verify. Lots of that going on. Feels sloppy to me. I like dedicated circuits.
Click to expand...
No the 73 is there, I was part of the "crew" that got it there. It may be Dodge vs Plymouth, AND THE WIRING IS DIFFERENT
 
There is no doubt at all that these girls can use more fuses. The earlier cars were even worse.
 
When using the factory schematics, get yourself a set of colored pencils. Highlighting the lines will make it alot easier to follow.
 
I actually use a combo of both. The way the 73 is drawn can be a brain screw. So I revert to the 72 and compare. ALWAYS compare and check

So far as Dodge vs Plymouth, there is no difference except stuff like whether a car has or could have come with a Ralley dash, etc etc. They are the same car. It's just that they WERE printed and sold separately, and that is the way MyMopar.com organizes them
 
SIX225 said:
When using the factory schematics, get yourself a set of colored pencils. Highlighting the lines will make it alot easier to follow.
Click to expand...
I am a bit of a nerd. Printed the electrical pages to pdf to reduce the size then put them in my tablet and opened with a paint program so I can use a stylus and draw on them. Have a set I am erasing as I go so I don't miss anything.
 
Looking good so far. I rewired my entire car except for the rear harness. I found the wiring colors for my 73 didn't exactly match the diagrams out there, but the schematics were correct.
 
Here are a couple of diagrams I put together when I was building my 75 Swinger.
Had to find a way to keep from blowing my brains out trying to interpret the manual.
FYI: the factory used the same color codes until 1976 for Plymouth and Dodges. They just added more colors as the added more STUFF.
I bought a 74 scamp as a parts car.( Running and driving )
As you can see there is an "outside" and "Inside" of the bulk head connector, showing what colors went where.
Hope it helps.

20230914_135604 (1).jpg


20230914_135621.jpg
 
Thank you for the notes. It has been helpful in trying to identify all the random parts. Finally finished up my wiring diagram but trying to figure out what type of wire to use and guages for everything.

I am thinking:

14ga primary for most stuff
18ga primary for relay coils
10ga TXL for the ignition relay switches
When I redo the engine compartment wiring for looks I'll be using TXL only I think.

Going to use a Bussmann RTMR 5 relay and 10 fuse block and maybe have the Other Lighting Relay be standalone.

The wiring in the drawings is what was ruined and needed replaced. From the bulkhead connector to the printed circuit board, the main harness wires are insulation welded into one cable with bare conductors poking out. Didn't attach the wiper wiring diagram because it is stand alone and fairly straight forward. I am currently reusing the AC/Heater wiring, rear harness, most of the engine compartment, and the interior lighting circuits because they were all stand alone and not damaged. I have the new wires sorted into smaller bundles for each major component.

I am also trying to find the terminal posts and pins to repair the printed circuit board, one post broke when removing the plug and several are loose. That and I would like to replace all the wiring and not splice onto the current pin. If I can't get regular post was thinking maybe a tiny screw and nut then put ring terminals on.

Any comments or suggestions would be appreciated because I plan on putting these in plugs with wire loom and heat shrink to hold the loom in place. Would be terrible to redo.
 

Attachments

  • Plan-Functional.pdf
    131.7 KB · Views: 110
  • Plan-Wire Diagram (1).pdf
    92.3 KB · Views: 106
Might want to search for my post "Modernized Wiring ..." maybe 10 yrs ago. Mostly underhood rewiring where I installed a fuse/relay box from a 1990's Jeep, in my 1964 & 65 A's and 1965 C. Under-dash, I added a relay for ACC to take that current load off the key switch and relays for the lift motor in my convertible. If doing again, I wouldn't use the Jeep box since the terminals are unusual and the plastic fingers which secure them can snap off, so the terminal will push into the base when you press in a relay. The Jeep box has ~11 relays as I recall. Later Mopars use half-size relays so the box can be smaller for the same functions.
 
On the connector pages I sent, show the gauges that are factory .
ie: Letter "Z" 18GY/R* (18 gauge gray with red tracer)
Be sure not undersize.
Good luck
 
BillGrissom said:
Might want to search for my post "Modernized Wiring ..." maybe 10 yrs ago. Mostly underhood rewiring where I installed a fuse/relay box from a 1990's Jeep, in my 1964 & 65 A's and 1965 C. Under-dash, I added a relay for ACC to take that current load off the key switch and relays for the lift motor in my convertible. If doing again, I wouldn't use the Jeep box since the terminals are unusual and the plastic fingers which secure them can snap off, so the terminal will push into the base when you press in a relay. The Jeep box has ~11 relays as I recall. Later Mopars use half-size relays so the box can be smaller for the same functions.
Click to expand...
I will look it up. I already purchase new Bussman relay boxes with mini relays and fuses.
 
triumphman said:
On the connector pages I sent, show the gauges that are factory .
ie: Letter "Z" 18GY/R* (18 gauge gray with red tracer)
Be sure not undersize.
Good luck
Click to expand...
I am only using 18 guage for the relay coils. Most everything else will be 14 guage since I am swaping to a voltmeter vice ammeter.
 
I got the in dash wiring harness removed and removed all the outer sheath that wasn't melted to the wires. All plugs are labeled and zip tied to make sure I maintained the branches and started verifying the standard wiring diagram to my actual wiring since changes had been make from previous damage. One major difference is that I have a seven fuse box with the ignition 1 line having its own dedicated fuse and going to some other stuff that I don't know what it is. I found a part number on one of the relays and referenced it, it could be a seat belt or low fuel relay? Not sure. The random plug down by the rear harness plug seems to run towards the rear of the car but I haven't pulled the carpet up to find out. I do show where the wires in the front run. I am attaching a simple drawing of the circuit in hopes someone might know what the extra is for. If worse comes to worse I will just replace the wire one for one since the car ran fine before the meltdown.

Having an air conditioned car showed some differences in the basic wiring diagram but were sort of addressed in the maual. Blocks W and Z of the bulkhead connector became air conditioning connections so block Z moved to A and W moved to B.

However I can't figure out what the brown with yellow trace in block C is, in the engine compartment it travels with the wires from A and B to the transmission and inside the car it goes to the random seat belt/low fuel relay I found along with the ignition 1 wire. In the drawing the brown and yellow goes from the transmission to the starter relay and I don't see it there on my starter relay but there is a tan wire that runs to a wire wrap with the wires from A,B,&C but does not come out so I am guessing it is spliced.

So far everything else is matching up with the 1973 Valiant Wiring Diagram and the 1972 Valiant Service Book. No 1973 Plymouth book, I will check the Dodge one to see if it explains my random stuff.

Thanks again for all the help.

Capture.PNG


20230926_103008.jpg
 
You must log in or register to reply here.
-

Back
Top