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HELP! Wiring complications

HELP! Wiring complications
As far as i can tell,from looking at the factory diagram. The brake failure switch should ground out to turn on the brake idicator light. the indicator light originates it feed from the ingnition switch. The emergency brake pedal also grounds out to turn on the brake indicator light.

hope this helps

I'm scared.... :dunno:
Would you know how and where (and which wire) to splice the brake failure switch into? This one splicing makes me worried... If I have the EZ wiring harness, would I still need to splice into the ignition for the brake failure switch or will it already be wired that way.. Probably not huh... :confused:
 
Since you have a 'Painless', I won't get into too much,
But "Painless" is anything but 'Pain-Less'.

You will have to wire your own dash, Gauges, ect.
You will have to wire your own charging system and ignition,
Most of the headlight harness isn't there either.

Painless is between $300 to $500 for HALF a harness...

--------------------------

As for the brake warning circuits,
Maybe this will help...

You ignition switch has more than one connector, and the connector is NOT marked for the brake warning light on most wiring diagrams.

BrakeWarnLamp01.gif


How this works is,
While you are cranking the engine, there is a MOMENTARY 'Ground' through the ignition switch, that will light the brake warning light,
When the key switch drops back to 'Run' position,
That 'Ground' is broken, and the brake warning switches take over.
Lets you know the lamp is working when you crank the engine.

----------------------------------------

Your dash cluster will go something like this,

DO NOT wire "57A Black" to the dash cluster if you haven't checked your ignition switch to make sure the 'Ground' is 'Momentary' during 'Cranking' and not a 'Ground' in 'Run' position.

You can't get an actual 'Jeep' ignition switch anymore, they are all "GM" switches that happen to fit the bracket and work for most things...

If you have the GM switch, and the 'Ground' is full time during 'Run' position,
Run the "57A Black" wire out the firewall and back like in the first diagram.

Otherwise, all your cluster wiring will be as shown.

GaugeClusterWiring01.gif


-----------------------------

Have you figured out your power feeds to the gauges yet?
IF NOT, PAY ATTENTION TO FACTORY SPLICE 'R' AND THE ONLY POWER FEED TO THE GAUGES IN THE SECOND DIAGRAM!

IF you hook up the power as shown in a lot of the 'Internet' diagrams, you will cook your gauges INSTANTLY...

When I'm building a custom harness for the dash,
I usually run "4A RED 18 Ga." to the gauge terminal from the fuse block,
Then take off from there for the rest of the terminals (4C, 4E) to the other stuff.
It also eliminates '4B' entirely.
Crimp 4A, 4C & 4E into the same ring terminal if you want to...

That takes a factory splice out of the wiring harness and cleans things up.
 
Last edited:
To be quite frank about it,
If you have $200 and some time, this really isn't 'Rocket Surgery'...

Some wiring tools, the correct terminals, some replacement connectors for the ones that didn't survive 30+ years, and you are off to the races.

The only 'Hard Part' is getting color coded wiring to match the factory stuff,
But with the internet handy, it's not all that difficult anymore.
And if you have a label maker, you can make the wires all one color and know EXACTLY what wire goes where...

I rebuild these harnesses all the time from scratch,
Almost all the connectors are out there, same with dash light sockets, side marker sockets, ect.
For about $200 and a few days, you can rewire the entire Jeep with little or no serious effort if the connectors are in good shape,
There aren't very many 'Molded' connectors you can't change the terminals in, or run entirely new wires with new terminals....

The best advice I can give you is to do a 300 DPI Scan of the factory wiring harness,
Make several copies,
Go in and color code all the wires in the circuits you are working on,

And 'Clip' or Erase the rest so they don't distract you while you are wiring the portion you are working on specifically.

Take it in small bites,
Ignition & Charging System (The most with molded connectors)
Then front end lights,
Then stuff like brake warning switches and horn, other small stuff,

Then rear lights, fuel sender, ect.

Then tackle the dash.
By that time, you will have enough experience with the 'Easy' stuff the dash will make sense,
(Dash, fuse block, flashers, brake light switch, A-C/heater motor, ect.)
 
Since you have a 'Painless', I won't get into too much,
But "Painless" is anything but 'Pain-Less'.

You will have to wire your own dash, Gauges, ect.
You will have to wire your own charging system and ignition,
Most of the headlight harness isn't there either.

Painless is between $300 to $500 for HALF a harness...

--------------------------

As for the brake warning circuits,
Maybe this will help...

You ignition switch has more than one connector, and the connector is NOT marked for the brake warning light on most wiring diagrams.

BrakeWarnLamp01.gif


How this works is,
While you are cranking the engine, there is a MOMENTARY 'Ground' through the ignition switch, that will light the brake warning light,
When the key switch drops back to 'Run' position,
That 'Ground' is broken, and the brake warning switches take over.
Lets you know the lamp is working when you crank the engine.

----------------------------------------

Your dash cluster will go something like this,

DO NOT wire "57A Black" to the dash cluster if you haven't checked your ignition switch to make sure the 'Ground' is 'Momentary' during 'Cranking' and not a 'Ground' in 'Run' position.

You can't get an actual 'Jeep' ignition switch anymore, they are all "GM" switches that happen to fit the bracket and work for most things...

If you have the GM switch, and the 'Ground' is full time during 'Run' position,
Run the "57A Black" wire out the firewall and back like in the first diagram.

Otherwise, all your cluster wiring will be as shown.

GaugeClusterWiring01.gif


-----------------------------

Have you figured out your power feeds to the gauges yet?
IF NOT, PAY ATTENTION TO FACTORY SPLICE 'R' AND THE ONLY POWER FEED TO THE GAUGES IN THE SECOND DIAGRAM!

IF you hook up the power as shown in a lot of the 'Internet' diagrams, you will cook your gauges INSTANTLY...

When I'm building a custom harness for the dash,
I usually run "4A RED 18 Ga." to the gauge terminal from the fuse block,
Then take off from there for the rest of the terminals (4C, 4E) to the other stuff.
It also eliminates '4B' entirely.
Crimp 4A, 4C & 4E into the same ring terminal if you want to...

That takes a factory splice out of the wiring harness and cleans things up.


HI TeamRush;105509!
Now that is a LOT of wiring to figure... It may take me some time. Thanks for the info. :notworthy:
 
To be quite frank about it,
If you have $200 and some time, this really isn't 'Rocket Surgery'...

Some wiring tools, the correct terminals, some replacement connectors for the ones that didn't survive 30+ years, and you are off to the races.

The only 'Hard Part' is getting color coded wiring to match the factory stuff,
But with the internet handy, it's not all that difficult anymore.
And if you have a label maker, you can make the wires all one color and know EXACTLY what wire goes where...

I rebuild these harnesses all the time from scratch,
Almost all the connectors are out there, same with dash light sockets, side marker sockets, ect.
For about $200 and a few days, you can rewire the entire Jeep with little or no serious effort if the connectors are in good shape,
There aren't very many 'Molded' connectors you can't change the terminals in, or run entirely new wires with new terminals....

The best advice I can give you is to do a 300 DPI Scan of the factory wiring harness,
Make several copies,
Go in and color code all the wires in the circuits you are working on,

And 'Clip' or Erase the rest so they don't distract you while you are wiring the portion you are working on specifically.

Take it in small bites,
Ignition & Charging System (The most with molded connectors)
Then front end lights,
Then stuff like brake warning switches and horn, other small stuff,

Then rear lights, fuel sender, ect.

Then tackle the dash.
By that time, you will have enough experience with the 'Easy' stuff the dash will make sense,
(Dash, fuse block, flashers, brake light switch, A-C/heater motor, ect.)


Hi teamrush,

I found most of the wiring harness "doable" (easier to install) but EZ didn't include any diagrams for my jeep, even-though, Jeep used a lot of GM products in those days.

I was able to get the tail, trailer and front end all wired up. but since the dash wires don't come with too many connectors and vague diagrams/pics I'm still researching one of the 'brake failure switch -the one that goes to the ignition and I can't figure if the Orange Cluster lights are supposed to go to the fuse box (splice into the Red Gauge power feed wire or in a whole different direction).

:poke:
 
Hi teamrush,

I found most of the wiring harness "doable" (easier to install) but EZ didn't include any diagrams for my jeep, even-though, Jeep used a lot of GM products in those days.

I was able to get the tail, trailer and front end all wired up. but since the dash wires don't come with too many connectors and vague diagrams/pics I'm still researching one of the 'brake failure switch -the one that goes to the ignition and I can't figure if the Orange Cluster lights are supposed to go to the fuse box (splice into the Red Gauge power feed wire or in a whole different direction).

:poke:

Best I could do on short notice for '76-'77 with factory fuse block.

If you have gone over to the dark side (painless) then you will have to find the dimmable dash lamps feed and hook up to that.

76-77DashLamps.gif
 
Last edited:
Best I could do on short notice for '76-'77 with factory fuse block.

If you have gone over to the dark side (painless) then you will have to find the dimmable dash lamps feed and hook up to that.

76-77DashLamps.gif
OOOO (hugs.--I don't see a image in the side selection for hugs, so I did my own). Thanks again for your awesome wisdom. :notworthy:
 
Your issues are exactly why I'm building some harnesses for actual Jeeps.
Year specific, fit better than original and have wiring that is sized for the application.

Notice there is more than one 'Orange' wire in that diagram,
There is one for all the dash lamps,
And one for the '4 wheel drive' light that goes out through the firewall to the Transfer Case .
It's a 16 Ga.
The rest of the dash lamps are 18 Ga.
 
Your issues are exactly why I'm building some harnesses for actual Jeeps.
Year specific, fit better than original and have wiring that is sized for the application.

Notice there is more than one 'Orange' wire in that diagram,
There is one for all the dash lamps,
And one for the '4 wheel drive' light that goes out through the firewall to the Transfer Case .
It's a 16 Ga.
The rest of the dash lamps are 18 Ga.

I know I'm a little late in responding but..... THAT WOULD BE TOTALLY AWESOME!!!:banana:Jeep REALLY needs to get a complete wiring harness kit out that has the right diagrams and connectors.. Then I CAN hook it all up fast...:drool:
 

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