Painless wiring kit?

[ShinyC10]

Hey guys, been wanting to order a complete new harness for my Chevy. I’ve had electrical issues somewhere throughout my truck for a few years now and have some figured out a way to stop my battery from draining over night but I had to put a battery cut off switch, sucks when it rains. Also, I’ve been putting off rust repair soooooo long that it’s too far gone so I’m gonna do a cab swap. I figured might as well do a rewire kit when I swap the cab out. Has anyone used a painless kit (10202# 28 circuit universal kit) for there squarebody. I figure 28 circuits is more than enough, might as well have more than I need than not enough if I want to add something . I have a few aftermarket electrical upgrades (radio, amps, subs). Was wondering how close this would be to the original wiring.

Thanks!

[chrismoore701]

I used a painless. Not quit painless. But was able to figure out. I had to repin a plug or two. And i think it is missing the dome light and the tailights. Enough to get there but need to add some to finish it. Overall it’s a nice kit. And fits in your existing home in the firewall. Which is the key part i wanted

[ShinyC10]

Originally Posted by chrismoore701

I used a painless. Not quit painless. But was able to figure out. I had to repin a plug or two. And i think it is missing the dome light and the tailights. Enough to get there but need to add some to finish it. Overall it’s a nice kit. And fits in your existing home in the firewall. Which is the key part i wanted

Sounds awesome. Did you use the 28 circuit? Kinda weird not to have the tail lights?? I figured that’d be a critical piece to a vehicle lol

[hatzie]

I assume your replacement cab has an internal wiring harness. If it's not 1978 or prior with glass fuses... Why not use it?
You can download the GM wiring diagrams for the new and old cabs then re-pin the bulkhead connectors if it's even needed.
Whatever you do don't just pitch the old harness and don't chop it up to remove it.

The original harnesses can be repaired in sections.
GM used a bunch of sub-harnesses assembled to make a whole.
The terminals for all of the stock connectors are available from Mouser and other online sources.
Many of the plastic plugs/shells/connectors are obsolete but they can usually be re-used. The part numbers for all the connectors in each year truck are in the wiring diagrams.
Molded connectors can be replaced with modern sealed connectors used on later model squares. Example: If your molded Packard 56 tail lamp bed connector is borked or the wires along the frame rail... I highly recommend using the 1985 and later square 4-terminal Weatherpak connector to replace it. It's easy, doesn't leak, and looks stock. This is why it's nice to have the wiring diagrams from 1973-1991 available... Look in my signature.
Tooling isn't that expensive even if you go with semi-professional grade tooling from Delphi Electronics.

The painless kits are anything but. They are not plug and play. They were originally intended for use in a Hotrod chassis with basic limited wiring.
If you're trying to avoid a lot of work by using one of those harnesses let me disavow you of that delusion right now.
The two I have experience cleaning up required extensive re-use of more than a few sections of the original in-cab, engine bay, and lighting sections of the original vehicle harness. I had to re-build sections of the original harness, that were damaged on the original and missing from the Painless wiring, using new terminals and wire. In the end, it would've been faster to just fab the damaged wiring.

Fabbing a sub harness or a repair section isn't that big a deal. Download the wiring diagram and print a blow-up of the section you're working with.
The wiring diagrams show the wire gauge of each individual wire in either AWG (prior to 1978) or MM² (1978-1991). I'd use SXL jacket wire. You can find SXL with various color tracer stripes on Evilbay. The stuff I've seen is sold by shops that build Motorcycle harnesses that are supplementing their income.
Use a piece of plywood and place nails where the endpoints, connectors, bends and, wire exits/breakouts are on the original harness.
Lay the replacement wires on the board one at a time leaving 2-3" of extra wire at the termination points. Each breakout and bend can be held with small wire ties. You can get bags of 1,000 from Home Depot.
Take a closeup picture of the wires exiting each connector to refer to when you are inserting the new wires in the old connector.
Strip and terminate each connection then extract the shell from the old harness and install it on the new one.

Wire harness tape is not electrical tape. It's a friction tape that lightly bonds when it's slightly stretched. You can use that or Split Poly or mesh sleeve or even split mesh sleeve .

[Richard2112]

Originally Posted by hatzie

I assume your replacement cab has an internal wiring harness. If it's not 1978 or prior with glass fuses... Why not use it?
You can download the GM wiring diagrams for the new and old cabs then....

Premium info. I've been wondering about some of those things. I also noticed that the connections on my truck are all copper and many aftermarket electrical are aluminum. Not a good mix.
Moreover, I believe the original wire insulation was engineered to not promote combustion. If one melts the insulation with a torch, the insulation will decompose but remove the flame and the fire dies. I wonder if this holds true of the available harnesses.

[ShinyC10]

Originally Posted by hatzie

I assume your replacement cab has an internal wiring harness. If it's not 1978 or prior with glass fuses... Why not use it?
You can download the GM wiring diagrams for the new and old cabs then re-pin the bulkhead connectors if it's even needed.
Whatever you do don't just pitch the old harness and don't chop it up to remove it.

The original harnesses can be repaired in sections.
GM used a bunch of sub-harnesses assembled to make a whole.
The terminals for all of the stock connectors are available from Mouser and other online sources.
Many of the plastic plugs/shells/connectors are obsolete but they can usually be re-used. The part numbers for all the connectors in each year truck are in the wiring diagrams.
Molded connectors can be replaced with modern sealed connectors used on later model squares. Example: If your molded Packard 56 tail lamp bed connector is borked or the wires along the frame rail... I highly recommend using the 1985 and later square 4-terminal Weatherpak connector to replace it. It's easy, doesn't leak, and looks stock. This is why it's nice to have the wiring diagrams from 1973-1991 available... Look in my signature.
Tooling isn't that expensive even if you go with semi-professional grade tooling from Delphi Electronics.

The painless kits are anything but. They are not plug and play. They were originally intended for use in a Hotrod chassis with basic limited wiring.
If you're trying to avoid a lot of work by using one of those harnesses let me disavow you of that delusion right now.
The two I have experience cleaning up required extensive re-use of more than a few sections of the original in-cab, engine bay, and lighting sections of the original vehicle harness. I had to re-build sections of the original harness, that were damaged on the original and missing from the Painless wiring, using new terminals and wire. In the end, it would've been faster to just fab the damaged wiring.

Fabbing a sub harness or a repair section isn't that big a deal. Download the wiring diagram and print a blow-up of the section you're working with.
The wiring diagrams show the wire gauge of each individual wire in either AWG (prior to 1978) or MM² (1978-1991). I'd use SXL jacket wire. You can find SXL with various color tracer stripes on Evilbay. The stuff I've seen is sold by shops that build Motorcycle harnesses that are supplementing their income.
Use a piece of plywood and place nails where the endpoints, connectors, bends and, wire exits/breakouts are on the original harness.
Lay the replacement wires on the board one at a time leaving 2-3" of extra wire at the termination points. Each breakout and bend can be held with small wire ties. You can get bags of 1,000 from Home Depot.
Take a closeup picture of the wires exiting each connector to refer to when you are inserting the new wires in the old connector.
Strip and terminate each connection then extract the shell from the old harness and install it on the new one.

Wire harness tape is not electrical tape. It's a friction tape that lightly bonds when it's slightly stretched. You can use that or Split Poly or mesh sleeve or even split mesh sleeve .

Thanks for the reply, and all the help you given me before.
So would it be easier if I got a complete harness from a junk yard and just replaced each wire from the junked one till I’m finished then swapped it into my truck? Pretty much rebuild the stock one outside of the truck

[hatzie]

Depends on how much of your harness is damaged and where.

Since you're pulling the cab and likely recycling it... Carefully liberate the harness from the rusted out scrap cab that you'll be getting turned into Chinese soup cans. It's a good piece to learn on.

It's really not as scary as it looks. You'll probably want to take several dozen pictures that you can print and write on.

Lay it out in an open area of the garage/barn or even on a nice day in the driveway.
Carefully examine it for rub-throughs and sections with the jacket melted or made brittle from shorting.

Usually, I've found the problem areas are where another owner attempted a quick-fix instead of actually repairing the problem area or where ham-handed "car stereo installation experts" or U-Haul "electricians" hacked up the wiring.

I've found green corroded wires twisted together with gooey old electrical tape covering them. No solder or crimp connection to maintain contact and much worse. Shake your head and make a list.

Scotcholok Vampire taps are the devil's own instrument. They open the wire jacket to any water and crud that can get inside. I've found wires that were corroded back 12" and further from one of these super duper "easy" connectors... Electrical tape just leaks slower and holds the water inside so it corrodes the snot out of the connection and wire even faster. Even if they are kept dry... the taps are Al and the wire is Cu... Galvanic corrosion anyone?

Look over every connector for thermal damage. This will happen where the terminal was damaged and plugged back in loose or the original connector wasn't sufficient for the amperage load in the circuit.
You'll need to use some common sense, forums, and even Google to determine what happened and whether the connector is really the right one. Thankfully there was a bit more oversight of the new EEs and interns when these vehicles were put together than there is now. I don't know of any connectors that were significantly undersized on these trucks. My 2009 Impala has known issue with a Metripak 280 connection in the rear window defrost circuit that's fused for 40A. The Metripak 280 carries 30A Max... see any problem there? My scorched RH kick panel harness connector was pretty crispy after one fall and spring. I replaced it and moved the defroster and two other too-big circuits to a Metripak 630 3 position connector and had the GM dealer replace the crispy connector under warranty.

There will be at least three harnesses in the engine bay that unplug from the bulkhead connector. Forward Lights, Engine, Wipers, Rear lights and fuel sender. The engine and wipers may be in the same connector. Your Heater or AC is a sub-harness. Dual tanks are another sub-harness. There are several others as well.

[ShinyC10]

Originally Posted by hatzie

Depends on how much of your harness is damaged and where.

Since you're pulling the cab and likely recycling it... Carefully liberate the harness from the rusted out scrap cab that you'll be getting turned into Chinese soup cans. It's a good piece to learn on.

It's really not as scary as it looks. You'll probably want to take several dozen pictures that you can print and write on.

Lay it out in an open area of the garage/barn or even on a nice day in the driveway.
Carefully examine it for rub-throughs and sections with the jacket melted or made brittle from shorting.

Usually, I've found the problem areas are where another owner attempted a quick-fix instead of actually repairing the problem area or where ham-handed "car stereo installation experts" or U-Haul "electricians" hacked up the wiring.

I've found green corroded wires twisted together with gooey old electrical tape covering them. No solder or crimp connection to maintain contact and much worse. Shake your head and make a list.

Scotcholok Vampire taps are the devil's own instrument. They open the wire jacket to any water and crud that can get inside. I've found wires that were corroded back 12" and further from one of these super duper "easy" connectors... Electrical tape just leaks slower and holds the water inside so it corrodes the snot out of the connection and wire even faster. Even if they are kept dry... the taps are Al and the wire is Cu... Galvanic corrosion anyone?

Look over every connector for thermal damage. This will happen where the terminal was damaged and plugged back in loose or the original connector wasn't sufficient for the amperage load in the circuit.
You'll need to use some common sense, forums, and even Google to determine what happened and whether the connector is really the right one. Thankfully there was a bit more oversight of the new EEs and interns when these vehicles were put together than there is now. I don't know of any connectors that were significantly undersized on these trucks. My 2009 Impala has known issue with a Metripak 280 connection in the rear window defrost circuit that's fused for 40A. The Metripak 280 carries 30A Max... see any problem there? My scorched RH kick panel harness connector was pretty crispy after one fall and spring. I replaced it and moved the defroster and two other too-big circuits to a Metripak 630 3 position connector and had the GM dealer replace the crispy connector under warranty.

There will be at least three harnesses in the engine bay that unplug from the bulkhead connector. Forward Lights, Engine, Wipers, Rear lights and fuel sender. The engine and wipers may be in the same connector. Your Heater or AC is a sub-harness. Dual tanks are another sub-harness. There are several others as well.

Well the harness inside the cab and the engine bay is pretty chopped up from the PO and a little from myself trying to figure out problems in the past.

Painless wasn’t my first choice, now probably out of the picture. I had saved Kwik wire to my desktop over a year ago cause I read good reviews about them and their kits look very nice

[Irish1941]

I have used American Auto Wire in my few last builds and it's pretty nice for a kit and saves time for sure.
https://www.americanautowire.com/sho...nel-wiring-kit

Like many on here, I try to build my harness when I have time. Takes longer but then it's exactly as I want it with room to expand.
Hatzie had a lot of good points that not many think about when it comes to wiring like bench building the harness.
My current truck has power window and locks that somebody hacked in. Hot all the time and a monster bundle of tape under the dash...ugh.

[ShinyC10]

Originally Posted by Irish1941

I have used American Auto Wire in my few last builds and it's pretty nice for a kit and saves time for sure.
https://www.americanautowire.com/sho...nel-wiring-kit

Like many on here, I try to build my harness when I have time. Takes longer but then it's exactly as I want it with room to expand.
Hatzie had a lot of good points that not many think about when it comes to wiring like bench building the harness.
My current truck has power window and locks that somebody hacked in. Hot all the time and a monster bundle of tape under the dash...ugh.

Ya mine has a bunch of tape under the dash. Was your AAW kit universal or the “direct fit”? Cause AAW is pretty pricey. I have my eyes on this kwik wire kit. Still 400 but supposed to be a great kit

[ShinyC10]

Originally Posted by Irish1941

I have used American Auto Wire in my few last builds and it's pretty nice for a kit and saves time for sure.
https://www.americanautowire.com/sho...nel-wiring-kit

Like many on here, I try to build my harness when I have time. Takes longer but then it's exactly as I want it with room to expand.
Hatzie had a lot of good points that not many think about when it comes to wiring like bench building the harness.
My current truck has power window and locks that somebody hacked in. Hot all the time and a monster bundle of tape under the dash...ugh.

Ya mine has a bunch of tape under the dash. Was your AAW kit universal or the “direct fit”? Cause AAW is pretty pricey. I have my eyes on this kwik wire kit. Still 400 but supposed to be a great kit

[Irish1941]

All I can do is offer what I went through. Not selling you on AAW.
I did Ron Francis and Painless back in '90s and was no easy feat then.
And I learned "direct fit" means maybe it'll work out for ya, maybe it won't.
Highway 15 is one I use for off road trucks and if you shop around less than $350.

No matter what you choose remember there will be more cost on top of the kit.
Switches, ends, shrink tube, loom & tape, proper crimper & dies etc...

[ShinyC10]

Originally Posted by Irish1941

All I can do is offer what I went through. Not selling you on AAW.
I did Ron Francis and Painless back in '90s and was no easy feat then.
And I learned "direct fit" means maybe it'll work out for ya, maybe it won't.
Highway 15 is one I use for off road trucks and if you shop around less than $350.

No matter what you choose remember there will be more cost on top of the kit.
Switches, ends, shrink tube, loom & tape, proper crimper & dies etc...

I’ve also heard great things about the highway 22. I’m gonna check it. Just wish someone had some experience with this kwik wire kits