Wiring diagram review

I'm ready to start pulling wire on the jeep and wanted to layout my wiring on paper before I started to hopefully minimize wasted fittings and wire. This is my first attempt at a full rewire and drawing a wire schematic so don't be to hard on me . This is on a 1980 CJ7 with a tbi350. I had the wiring harness cut down and computer flashed already so some of the references you see on the drawing are for wires coming out of the harness. I didn't put the gauges on here since they're all mechanical. You'll also notice there are a few spaces left blank for fuse size and that's due to me not knowing what size fuse to put in there. I'll post the drawing through tapatalk since photobucket is being difficult.

Sent from my iPhone using Tapatalk

I may be missing it bc my head it turned sideways laughing1 but are you doing a push button ignition? flip switch fuel pump?

The biggest thing right away is you need some sort of battery disconnect. The way you have it now, everything will always have power. You can either disconnect the + battery or the - ... pros and cons to either.

slravenel said:

I may be missing it bc my head it turned sideways laughing1 but are you doing a push button ignition? flip switch fuel pump?
The biggest thing right away is you need some sort of battery disconnect. The way you have it now, everything will always have power. You can either disconnect the + battery or the - ... pros and cons to either.

Click to expand...

Everything is run off of rocker switches. I have a battery disconnect switch in the garage that I can install between the battery and relay/fuse block.

Correct me if I'm wrong though, but with each of the switches turned off, nothing is receiving power as it's currently laid out and the disconnect switch would act as safety to ensure nothing was drawing the battery down while not in use.

Not sure if it matters, but this is the switch/gauge cluster


Sent from my iPhone using Tapatalk

as it is there, at all times your relays, fuse block, alternator, starter etc etc all are carrying power all the time. While they aren't "doing anything" with that power....its still there, and it is my opinion that I don't want power to go to anything uncontrollably. Alternator and Starter having power arent necessarily bad, but there is still going to be a hot cable running from battery to those things at all times with no way to stop that power.

You will want to be able to shut it down completely - and there are several ways to do that. In everything that I have ever built I have put in at least 1 (my current buggy has 2) fail-safe switch that shuts the entire thing down. A guy I know had his buggy burn to the ground because his alternator or starter cable (one of the two, I can't recall) shorted out under a panel that he couldn't get to fast enough and just sat there and arced until it caught **** on fire.

Fire, bad crash, an arcing short, a cut wire, etc etc etc are all reasons you'll want to shut it down.

Punkin85 said:

Everything is run off of rocker switches. I have a battery disconnect switch in the garage that I can install between the battery and relay/fuse block.

Correct me if I'm wrong though, but with each of the switches turned off, nothing is receiving power as it's currently laid out and the disconnect switch would act as safety to ensure nothing was drawing the battery down while not in use.

Click to expand...

I am not good with wiring or circuitry at all but I did the same thing, put a cut-off between the battery+ and the relay block. But for some reason, if I kill the cut-off while running it continues to run for about a minute. I'm only mentioning it because it seems like there's more to it than just throwing a cutoff in the positive feed.

Beerj said:

I am not good with wiring or circuitry at all but I did the same thing, put a cut-off between the battery+ and the relay block. But for some reason, if I kill the cut-off while running it continues to run for about a minute. I'm only mentioning it because it seems like there's more to it than just throwing a cutoff in the positive feed.

Click to expand...

There is. The alternator will keep things running for a bit if you just put it like that.

Give me a second and I can kinda draw out how to do it

OK here are the options...



the top one is how I had my old buggy. This would make the switch cut all the power...but this would allow the alternator to continue charging once cut and would keep power going to the starter and the power distribution block (and then every accessory down the line)

the bottom on is what I have now to allow me to kill the power to all of the accessories, but keeps the alternator "hot" wire from running all the way from the back of the buggy to the front (since my battery is behind my seats, I have a cable running all that distance and I wanted a way to cut its power). Adding in the 2nd switch right at the battery allowed me to kill that hot wire as well in terms of a total **** hitting the fan situation

The top one will not kill the motor when you flip the switch. Make sure the alternator charge wire is run to the battery side of the switch, if you're trying to use the switch as a master kill.

If you're only wanting to use it as a battery disconnect, then wire it on the Load side of the switch.

This way I have both a battery disconnect AND a master kill switch.

Full disclosure though...you don't technically need 2 switches and probably 99% of guys are only running the 1. Its just up to you and how you want it all to react.

I'll probably add a disconnect. Thanks for the input.


Sent from my iPhone using Tapatalk

So with adding a disconnect switch, can someone give some guidance on what wire size for these runs:

• Battery to disconnect switch
• Disconnect switch to inline relay fuse
• Disconnect switch to fuse block
• Disconnect switch to starter

Punkin85 said:

So with adding a disconnect switch, can someone give some guidance on what wire size for these runs:

• Battery to disconnect switch
• Disconnect switch to inline relay fuse
• Disconnect switch to fuse block
• Disconnect switch to starter

Click to expand...

Somewhat depends on distance between them but I used high quality 2/0 welding cable for almost all of that. Some #2 in there also depending on where and what...but mostly 2/0 for the main cables.

www.weldingsupply.com is where I bought it all.

slravenel said:

Somewhat depends on distance between them but I used high quality 2/0 welding cable for almost all of that. Some #2 in there also depending on where and what...but mostly 2/0 for the main cables.

www.weldingsupply.com is where I bought it all.

Click to expand...

Thanks for all the tips, I really appreciate it!

I suck at wiring, I was dizzy with trying to follow that drawing. I was wondering if someone had a picture of a more linear lay out, if that makes sense. It won't be long and I will be doing mine

You have fuses before your relays also, do you need 2 separate fuse blocks? Or can you just one big fuse block and use 7 or ever how many you need to power your relays?

Dirt700 said:

You have fuses before your relays also, do you need 2 separate fuse blocks? Or can you just one big fuse block and use 7 or ever how many you need to power your relays?

Click to expand...

You could use a second fuse block if you wanted, I chose to use inline fuses for each since I didn't have a good place to mount another fuse block.


Sent from my iPhone using Tapatalk

Just an update, I finished the wiring tonight and everything worked as it should. The wiring diagram made the project a lot easier. I would recommend it to anyone who is like me and unfamiliar with wiring.


Sent from my iPhone using Tapatalk

Starting to try to figure out the wiring crap, this is what I came up with so far. I know I need a fuse block somewhere before the relays. Only thing that I want run off switches is light and radio and I want to be able to turn them on any time

Sent from my XT1585 using Tapatalk

You want the alternator to be wired BEFORE the battery disconnect, otherwise it will back feed current in the system when you're trying to cut it off.

Also, you can't feed current to all those things (Fuel pump, fans, starter solenoid) from a single ignition switch.

I would do this :

Bebop said:

You want the alternator to be wired BEFORE the battery disconnect, otherwise it will back feed current in the system when you're trying to cut it off.

Also, you can't feed current to all those things (Fuel pump, fans, starter solenoid) from a single ignition switch.

I would do this :

Click to expand...

So... Straight hot wire to the relays? Then toggle switch to the ecm and starter button?