No such thing as a factory alarm on XJs. All you get were RKE and SKIM

 

I don't know if you realize this but if you hook your lights to the same output as the horn, they will flash very quick and short. Most if not all factory and aftermarket entry systems flash the lights much longer than the horn sounds. If you are ok with this then certainly you can hook it up to the horn. I was just letting you know it's not going to flash like other factory or aftermarket systems out there.

 

that's when you get yourself a time delay relay and the lights will come on and stay on for however long the relay allows for.... a defrost relay for instance only needs a quick signal to turn on and then stays on for however long it was designated too.

 

Hi

Just got to see this post, sorry I did not reply before.
The 12V webpage has the information you need, if you look at the alarm section for a 2000 Cherokee, there is information about the drivers lock and unlock wires, and also for the parking lights, (wire color, location and polarity) this information can be used for your amber lights to flash (not sure but amber lights are the same ones as parking lights?)

However there's a catch, if you just splice them, they will combine every pulse and that will lead to potential short circuits.

Diodes need to be used, to allow the flow of electrical current only one way, and therefore not combining any pulse.

Also, as it was mentioned, the pulse sent by the lock / unlock is pretty small in time, less than half a second, therefore if you want to extend such pulse you will need a time delay, in the past I have used the 528T time delay, which is adjustable from 0 to 10 seconds.

If you noticed in the wiring info on the picture, the parking lights are activated by a positive signal, and the lock / unlock pulse are negatives, another reason for a relay to be used.

So the wiring will be as pictured, from the drivers lock wire to a diode and then to the 528T relay, same with the unlock wire
After the diodes the wires are spliced into a single wire: the Black with stripe wire on the 528T.
Black and red on the 528T should be connected to earth and 12V constant.
Blue loop should remain uncut
The yellow should be provided with 12V, can be spliced with the Red one
Finally the Brown wire from the 528T can be spliced with the Black/Yellow wire on the Light switch

Next step will be to give it a try, I will recommend an inline fuse at the RED wire, just to play safe, you will need to adjust the relay (using a small flat screwdriver) for the desired time and this should be it

Looks a bit complicated but it is not, just splice a few wires, no cutting on the vehicle harness is needed, just to splice 5 wires:
driver's lock wire
driver's unlock wire
Constant 12V
Ground
Parking Lights wire

Hope this helps you out!

 

sorry to revive an old thread. my keyless entry horn doesnt honk.. my inside light turns on when i unlock but i would like to find a way to get a better idea when i lock and onlock the car... i have a 98