47-55.1 where did you bring in the orignal S10 harness on a 49 cab?

[hodag]

Hi Everyone! I have another question. I am using everything I can including the wiring harness. How did everyone run the harness into the cab. I was thinking of putting back in where it was on my 1994 S10 under the passenger fender into the side wall.

I would like to hear from you all that used the S10 harness and what location did you go into the cab. Also what you kept and striped from the harness to use.

Thanks Everyone. You have shown me a lot of great ways to do this conversion to my 1949 cab.

[joedoh]

I have done this a few times, what you are thinking is right, put it through where it went through originally. it makes it easy to hook up without needing to extend the wires.


i will find some pictures, what i did was cut the s10 firewall around the wiring pass through, and welded it in the old truck firewall

[dsraven]

ok, listen up, if anybody knows an AD S10 swap it's joedoh. he's done so many he prolly lost count.

[oldman3]

Originally Posted by dsraven

ok, listen up, if anybody knows an AD S10 swap it's joedoh. he's done so many he prolly lost count.

X2...Jim

[mr48chev]

Originally Posted by dsraven

ok, listen up, if anybody knows an AD S10 swap it's joedoh. he's done so many he prolly lost count.

Yuppers, Joedoh is the go to knowledge base on the S-10 thing.

Where you run them through the fire wall may depend on if not having to do a lot of extra extending with the wires on the inside is more important than having a clean clutter free firewall. Any time I see the hidden down there thing it says that the builder is shooting for clutter free.

[hodag]

Originally Posted by joedoh

I have done this a few times, what you are thinking is right, put it through where it went through originally. it makes it easy to hook up without needing to extend the wires.


i will find some pictures, what i did was cut the s10 firewall around the wiring pass through, and welded it in the old truck firewall

Look forward to pictues. I cut out the wiring mount hole out of the s10 to put in the 49.

Getting close to doing this. thanks.

[joedoh]

sorry for the delay, i only keep about a years worth of pictures on my lappy, the rest get sent to the archive on my home machine. when i need old pictures its a step or two more haha.


two of these are 41's, but its the same idea. i am not sure what harness you are using though so these pictures cover the 85-91, the 92-97, and the 98+. call me farmers because i have seen a few things haha.

[Second Series]

I cut off the bulkhead connector and stuffed the wires through the original hole.
This is for an ’88 K2500 to a ’47, but the connector looks the same.
There are Four wires for the wiper motor that won’t be used, Courtesy lamps, and I don’t remember why I crossed out the clutch wire. There are 6 connector locations that are empty. I’ll run the wires for the front and rear lights and fuel tank through the other existing hole in the firewall. I added signal names to the diagram, but this is for the ’88. It looks like the connector layout was changed every few years.

[hodag]

Thank you guys this will help alot!

[hodag]

Originally Posted by joedoh

sorry for the delay, i only keep about a years worth of pictures on my lappy, the rest get sent to the archive on my home machine. when i need old pictures its a step or two more haha.


two of these are 41's, but its the same idea. i am not sure what harness you are using though so these pictures cover the 85-91, the 92-97, and the 98+. call me farmers because i have seen a few things haha.

Have you ever put out a list of wires need and not needed when putting the S10 harness in. That would be a help along the way for me the beginner. Thanks Joe!

[dsraven]

you can get a wiring diagram from your local parts store or online and do the pinouts easy enough. you just gotta know what you want to use and what you won't use. then find those wires in the harness and unpin them. there are plugs that go where the wire used to be if you want it water tight.

[joedoh]

Originally Posted by hodag

Have you ever put out a list of wires need and not needed when putting the S10 harness in. That would be a help along the way for me the beginner. Thanks Joe!

I use everything! all the functions on my trucks, HVAC, drivetrain, even the steering column switches, everything. so I couldnt help with what to cut out aside from the abs wires.

you can probably find a wiring diagram for your year online though, and then its just figuring out what you are keeping.

[Father&son56project]

The advice from Joedoh and Dsraven is bang on. Get a wiring diagram for the ‘94 S10 and SLOWLY remove the unnecessary stuff. I emphasized “slowly” because there are hidden junctions in that harness and you can create problems by quickly ripping out wires. The wiring diagram will let you “logic things out” before you start clipping & depinning stuff. With a paper copy of that diagram on hand, use some coloured pens or markers to note the changes you made, or future debugging will be really tough. Also, do one system at a time. That way you can check that everything else still works before you head on to the next system.

I used this approach on my ‘96 S10 harness, removing stuff like radio, courtesy lights, trailer harness, side marker lights, portions of the HVAC system, front wheel speed sensors (not needed as I removed ABS), wiper system (mine is 1 wire and inside the cab), seat belt sensors, etc. Even after all that, the under dash harness is still huge! I may try again next winter after I run the truck around for a while (I am just about ready to put it on the road for the first time).


The DRL (daytime running light) feature adds a ton of wires to the system, and I was hesitant to touch it as this was my first time doing a swap, but if I can figure out how to rip that out I will really clean up my harness. But I will follow my own advice and SLOWLY do that, by removing a wire, testing, removing another wire, testing, and so on.

You of course can also do what Joedoh does and use the original harness and switches as-is, and not have to fool around with anything!

Hope this helps

[dsraven]

father and son has some good input there, remove the split loom and parse out the circuits and label the connectors for where they go and what they do because some circuits feed others and simply unpinning stuff can affect another circuit you want to use. pay attention to the ground circuits as well because there will be a bunch of ground wires connected to a single ground connection. I recommend to install a good dedicated ground from the battery to the cab sheet metal on a good clean bare metal surface and when done all the wiring then go back and insulate that spot from the weather. use a star washer on the bolt (notice I said bolt and not screw) for a good connection, like a stock, newer, vehicle would have
before unpinning or working on the harness take a few pics of the plug ins from a couple different angles. put some mask tape on them so you know which plug in the
pic is from where etc. that will help you later on if a diagnosis is needed
joedoh has it right, use all the stuff you can from the original harness, thats why they are called "donor trucks".