Ah, hahaha! I did it! I successfully integrated an OEM RF keyless entry receiver into my 1992 Cherokee Laredo. (A little cheating was involved but I believe it to be more or less authentic
SO, for those of us who own an XJ Cherokee --with power locks, of course-- built between 1987 and 1996, we are familiar with the dreaded infrared key-less entry remote and dome receiver. Originally an accoutrement of the Renault, the system was awesome in its heyday, but certainly lived long into functional obsolescence; its inefficiencies and restrictions are ones that could have been designed out
, but this process was long and slow for some reason.
When I bought my 1992 Cherokee Laredo, half of the reason I did so was because it still had its working --original-- one button "Neiman" key-less entry remote!! A horrid system though it was, I was swayed by the novelty of having it; I don't think I had ever even seen one in real life before that day. Everything was cool until the remote finally bit the dust. An internal chip broke free from the circuit board; I tried to solder it, but ruined the transmitter in the process.
After my loss and subsequent period of grieving, I decided that I was going to have a "new" key-less entry system. Being a hard-core Jeep man, however, I resolved that the system that was going into my car was going to be a "Jeep" one; there would be no aftermarket crap in my baybay.
Thankfully 1992 was the last year of the "single button" "dealer programmed"
remote, and with the 1993 model year came an upgrade to a "dual button" "me programmed" remote; it was still IR, though. GRRRR. I figured that my '92 XJ, being on the cusp of this change, would probably support a 1993 RKE system with relative ease of integration and minimal pain of re-engineering. I was right. I successfully installed an IR system from a donor 1996 XJ Sport into my '92. It was nice to finally be able to choose between lock and unlock, and also to be able to program the remote transmitter myself without having to deal with the dealer$. (For those who may be interested, it isn't actually that hard to do for the 1990-1992s. The 1989 and priors are trickier, however. I've not successfully done one yet, but I can visualize most of the system and I don't think it would be impossible.) The only downside to my upgraded system, of course, was that it was still IR. I had to have the damn remote up against the window, pointed at the receiver as closely as possible in order for it to work.
LOOKING FOR A BETTER SOLUTION, I started checking out sites to see if anyone had successfully integrated an OEM RF system into one of the pre-1997 XJs or pre-1996 ZJs. So far, there's no info. One thing I certainly learned was that one is absolutely disallowed from programming his/her own remote with these post 1996 RF systems; subsequent lessons would teach me that it is effectively impossible. Thanks Chrysler.
Feeling confident in the beginning, despite this obstacle, I purchased a receiver --extracted from a 1998 XJ Limited-- from the junkyard. I also picked up two transmitter remotes, one from a 1996 ZJ (shaped like a rectangle), and one from a 1999 WJ (shaped like an "8"), both were tested and functional; I figured that one was bound to work. After mapping out the wires and doing extensive kamikaze engineering, the system was remained to be a no-go. It's safe to say that the DRB scan tool is, in fact, mandatory to program these stupid systems. My Jeep, not being equipped with an OBDII port, leaves me screwed. Fabulous.
NOT GIVING UP IS A VIRTUE. During my research, I noticed how the 1996-1998 rectangular remotes are very similar in design to those of GM automobiles of the same time period.
I learned that both Chrysler and GM cars --for a brief time-- shared a RF system produced by "TRW Automotive."
After a bit of research, I determined that this system is not only compatible with Jeeps, but it's also simple to install, and best of all, allows one to program his/her own remote(s)!! Of all of the GM cars, I determined that the best system to recover is one from a 1993-1995 Chevrolet Camaro or Pontiac Firebird (it's the same car). The RKE module is located right under the passenger's side kick panel. There is also a wonderful website that I must give credit to for having assisted me with this. It lays out a complete and accurate wiring schematic for the system. <http://berlinetta.info/KeylessEntry.htm>
The RKE module I used in my Jeep was removed from a donor 1994 Firebird. The new module is beefier than the IR "Jeep" one I took out of my overhead console, so I moved it to a space underneath the passenger's side dashboard next to the TCU. It fits snug. This is also a good place for it, because all the wires needed to connect it are underneath the passenger's side kick panel. Bearing in mind that this application was specific to a 1992 XJ; other applications may have different wire color codes. The wiring is as follows.
On the Jeep Side On the TRW module side
Blue/red (dome lights)-----White
Pink/purple (unlock)-------Tan (there are two tans use only one)
Orange/black (do not use)
Red/black (do not use)
Pink/black (do not use)
Black ("Panic" or "Trunk Release" not equipped.)
Black/white (ground for remote programming mode)
Once the module is installed, turn the key ignition to "ON" but not "RUN." Ground the Black/white wire. Within a few seconds the door locks will cycle. press and hold BOTH "lock" and "unlock" buttons on the transmitter. The locks will cycle again if and when the remote is accepted. Program any other remotes at this time, this way, as well. Once the ground is removed and the key ignition is turned "OFF," the transmitter data will be stored in the receiver. If the wire is re-grounded, all data will be lost and the remotes will need to be reprogrammed.
Remember that 1996 ZJ remote I purchased? I was able to program it directly
to this RKE module! This means that the remote I'm using is a genuine "Chrysler/Jeep" RF remote which now operates the key-less system in my 1992 XJ! (the remote even has a "Chrysler" logo on it!)
Also, that 1999 WJ remote I mentioned earlier is not compatible with this system. I tried to program it and it didn't take; this despite also
being a TRW Automotive product(!)
So there ya have it!
Anyone can now have an "official" Jeep RF RKE system in his/her pre-1997 XJ! My remote now works up to about 20 feet away and I don't need to be pointing it at the car.