Remote Keyless Entry System - Attaching more lights

I have a 98 XJ Classic. I recently installed some rock crawling red LEDs on the bottom.

I thought that other than just looking cool, it would be great if they came on when I clicked the remote to unlock the doors. It would be a great way to see where your feet ended and the Jeep began.

I've dug around the Internet and a XJ manual, but I cannot find any detailed information on the OEM RKE. I found a couple of signal input/output for the RKE module, but I cannot find out where the RKE module actually is!!!!

I thought about just tying into the dome light, but I'd rather have the RKE control the bottom lights, I really don't want them coming on when I turn on the dome lights with the headlight switch (rotate until the dome light comes on).

I may have found a clue!!!

"Dont have a factory OHC. It was in my dome light housing"

muckleroy said:

I may have found a clue!!!

"Dont have a factory OHC. It was in my dome light housing"

Click to expand...

Cool. Keep us informed!!! :cheers:

Ok here is what I have found so far, and it isn't much...

Based on the information that the RKE (Remote Keyless Entry) module was located in the overhead console (I don't have one but looked up anyway) I found it in the dome light housing. (see image below)

As you can see here (the colors are a little off in the pic) the black wire is the ground, the yellow wire is the signal wire to the dome light, and the red wire is a constant 12 volts.

What I expected was that one of these wires would be 0 volts and then go to 12 volts when the RKE was signaled. What I found was that the yellow and red wires have 12 volts. The dome light is off. I signal the RKE and the dome light goes on, the yellow wire voltage drops to 0. After about 15 or 20 seconds the dome light goes off and the yellow wire's voltage returns to 12 volts.



My first thought was attaching a normally closed relay to the yellow line and attaching the relay to my rock lights. Not a bad idea having the lights on their own relay. The problem I have is that the relay will have to be energized the entire time!

I'm going to keep digging around. I switched my major from electronics to computers in college. I wish I had more electronics now! I was hoping for a 12 volt on signal from the RKE, instead I have a 12 volt on and a 0 volt to turn on the dome light!!!! arg....

I purchased a standard automotive relay. It will switch 12v if the relay is energized, or off. Basically I was going to hook up the relay to the yellow wire, but use the post on the relay that switches the 12v when the relay is off.

After doing some more research, and checking the current draw of the relay when on, it was 170 milliamp. 25 milliamp max is recommended constant draw on a car battery.

So now I need to find a relay that will switch 7 amps but only draws about 25ma since it will be on all the time, except during the time the RKE is activated.

I was thinking of a voltage inverter, but even that will have a current draw.

Nothing is ever easy! lol

BTW, I'm digging around in the dark here. If anyone has some information on this please share.

Ok I'm an idiot. I think a "normally closed" relay would have 0 current drain... More to come...

Still watchin'!! atriot:

:cheers:

just do as the dome light does and use the red and yellow wires.
wire it in parallel across the dome light, and when the dome light is on, the LEDs will be on

:idea:



Yep, I found this one just after my last post. It is almost identical. I was considering running from both the yellow and red wires, but after your suggestion that is what I will do. Thanks!

The only thing I am going to do in addition is put in a diode so when the coil distarges it won't fry the RKE.

good call on the freewheel diode. i fixed the schematic for future reference.

h2opete987 said:

good call on the freewheel diode. i fixed the schematic for future reference.

Click to expand...

As Curly from the Three Stooges used to say, "If at first you don't succeed keep on sucking until you do succeed, nauk nauk nauk"

Done, and in the bag. One thing though. You don't switch the 12 volt, you have to switch the negative line.

So just like the drawing above but connected to the chassis ground and the ground for the LEDs.

LED rock crawling lights now come on as does the interior dome and foot courtesy lights when you press the UNLOCK on the remote.

The LED rock lights also come on when the door is opened.

The switch that I installed to turn the LEDs on and off (and flash) still functions.