Help- Identifying wiring for lights.

Hi,

Just bought a Cherokee (Liberty to you guys). I've always been a Land Rover driver - 25 years or more, but I'm getting soft so I bought a Liberty :-) .... and I love it.

Anyway, I will be using it for towing, and I mounted the towbar and set about the electrics .... and stopped.

I don't have a manual yet so have no wiring diagram for the rear light clusters. I tried a test meter to try and work out which terminal was whichin the connector block but since they all earth through the same terminal, using a test meter just shows every two terminals as connected.

Can anyone out there identify the colour coding for the lights for me. I can't get a Jeep Liberty manual by the weekend and I need to have the trailer lights wired for Friday!

Ewan Scott

Reply to
Ewan Scott
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If you just try to 'tap' into the brake and running lights you will set off an error code in the computer.

The quickest solution is to by a pigtail that just tees into the system .

It will be available at your dealer or any place that sells or installs trailer hitches.

Reply to
billy ray

I've got what I guess you call a pig-tail, it is a bypass that doesn't mess with the vehicle's electrics.

So I can tap into the rear lighting if I can identify the colour coding.

I have as follows:-

Near Side Rear Indicator - Green and Red Cable Off Side Rear indicator - Brown and Red Cable Fog lamps - Brown and White Cable Offside Tail Lamp - Green and Yellow Nearside Tail Lamp - Black and Yellow Brake Lamps - White and Orange Reverse Lamps - Black and Green Earth cable Black and White

Offside and Nearside would be Driver and Passenger side - However, since you guys sit on the wrong side of the vehicle to drive they would be the other way around :-)

If I've got the colour codes correct I'd be obliged if someone could let me know one way or the other. Otherwise I'll just have to go and buy a bulk lot of fuses :-)

Thanks for any help.

Ewan Scott

Reply to
Ewan Scott

You would also need the 'black box' that sits between the present wiring and your proposed new wiring that powers the lights independently from the vehicle lights.

Reply to
billy ray

Yup, that looks similar to what I have.

So how abouit those colour coded wires? Thanks .

Ewan Scott

Reply to
Ewan Scott

I can send you the information from an WJ (or an older XJ) but I don't know that is the same for the KJs.

Who has a Liberty manual and can check the wiring diagrams?

Reply to
billy ray

Personally, I'd be using a buddy to hit the brakes for me, and I'd look for

12vDC. then, I'd turn the lights on and look for another 12vDC. Finally, I'd turn the blinker on and look once again for the 12vDC. If only one circuit is activated at a time, then the 12vDC should move around with each check, and only appear once with every check.

Reply to
Jeff Strickland

Thanks for the responses.

I dismantled a tail light assembly and worked out which terminal was which and worked it backwards.

So for anyone else doing thie job with an aftermarket bypass unit.

Left Side Rear Indicator - Green and Red Cable Right Side Rear indicator - Brown and Red Cable Fog lamps - Brown and White Cable Righ tside Tail Lamp - Green and Yellow Left side Tail Lamp - Black and Yellow Brake Lamps - White and Orange Reverse Lamps - Black and Green Earth cable Black and White

The live feed for the bypass unit is supposed to be run from the battery live, with a 15 amp in-line fuse.

However, it can be tapped into the live feed to the rear power outlet (pink and black), which is always live.

Somewhere someone asked about removing the rear right panel for access to the lighting block. ..

Unclip the rear deck trim and the rear roof trim. There is a single plastic philips head screw with a luggage retaining ring, (not that it would retain very much at all), when you try and unscrew this it will chew up.

Lever out the side panel along the side of the rear frame and open it out carefully to access the right wing block in the rear wheel arch well (fender well).

If you lift the rear carpet there is a rubber seal about 1.5 inches in diameter. If you puncture this you can run your trailer lighting cable down through this without breaking any seals or drilling clean metal.

Hope that can help someone somewhere.

Ewan Scott

Reply to
Ewan Scott

I do not know this for sure, but have been informed (and it makes perfect sense) that the rear or any other 'power' outlets, vs cigar lighter outlets runs through the computer for voltage regulation to have a stable 12V supply for things like electronics.

This means if you have any issues with the trailer lights shorting or failing, which can/does happen, you are very likely to cook the main vehicle computer. This would be a 'very' expensive error.....

I would highly recommend a dedicated fused power line for the trailer power.

Just FYI, 'most' portable electronics are fused with a one or two amp fast blow glass tube type fuse. The plastic automotive fuses are not fast enough to prevent computer chip failures from power spikes or shorts so even a fused lead to the trailer lights from the regulated source wouldn't likely stop main computer damage in the event of a short.

Or I could be totally mistaken and the feed is straight 14V+ battery/alternator power, but I sure don't think so....

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: N>
Reply to
Mike Romain

That does raise an interesting point. In my WJ the "power outlet" is hot full time where my 'cigar lighter' is only on with the key.

As you know I did manage to run my battery dead with that 12v electric cooler running through the power outlet. If that went through the computer I would hope that they would have included instructions to shut off the power before the battery went dead.

Reply to
billy ray

I recommend more than that; DC's OEM kit specs relays that draw directly from the battery post, AND seperate fusing for every circuit beyond the rear bumper. It also plugs directly into an existing rear wiring harness using waterproof connections. Very nicely designed. Unfortunately, unless you use a DC OEM receiver with the specially-designed waterproof RV outlet box on the side, you'll have to wire your own outlet.

Consensus: use seperately-fused circuits for trailer power, and/or relays for all circuits if possible for the best protection and reliability. Wire everything directly from the battery, not from existing circuits. It's a PIA, but you'll never have a problem with it later on if you put in the effort.

-JD

Reply to
JD Adams

Does the existing harness have a clean power line for their box or is a new line required also?

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06
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Reply to
Mike Romain

It uses a custom 'pass-through' plug that hooks into an existing harness up underneath the left-rear fenderwell. Nice design. No splicing or wire-cutting required. The relays and pass-through connector are all one single waterproof unit that all nylon-tie together and tuck neatly back up underneath the fenderwell.

Three wires route along the frame rail to the engine compartment: ground, 12V+ and trailer brake actuation, which also has its own relay. The fused 12v+ lead is connected directly to the fuse box + terminal, and supplies power for all trailer lighting and brakes. A standard RV connector is used for the trailer hookup. DC's OEM receiver has an insulted RV connector box welded right in, so it was a perfect fit.

It sounds more complicated that it actually was and I was surprised at how easy it was to install. I loathe wire-tapping/splicing - it always manages to corrode and cause problems. For about $35 bucks, this is a great way to custom-wire a trailer hitch on a TJ. I bought mine from:

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Reply to
JD Adams

On the basis of better safe than sorry, I'll run a cable direct from the battery. Thanks.

Ewan Scott

Reply to
Ewan Scott

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