Twisties

A little background is probably in order. This is a new to me 97 Sport, 4.0l auto. I've had it for a few weeks and have decided to make a few minor upgrades. It's been running great, have had no issues, even swapped in a complete 2000 XJ cruise system that is working flawlessly.

It was originally equipped with RKE, the board is still in place, but did not come with fobs. I acquired some used fobs, the local Jeep dealer was going to program them for a very modest amount. Took it to the dealer and they tried for almost an hour and came back and said that the original PCM had been swapped for a 1999 PCM and that it wouldn't communicate with the 1997 RKE. They suggested I find a 1997 PCM to swap in and give it another shot.

First question: Does what they're saying make sense?

Second question: Is a 1997 the only version that would work or would other years work as well? I understand there were some changes 1998+, but would a 1996 work? I'm asking because there's currently no 1997's at any of the local JY's.

Thanks in advance for the help!

CCKen

Check the part number on the decal on your PCM.

If its a '99 the part number will be 56041 492AC.

The '97 part number is 56041 277AD.

These part numbers are for a 4.0, auto trans, federal emissions.

I don't think a '96 PCM will work because it's a Rube Goldberg XJ. Alot of changes took place jumping from the '96 to the '97.

The '97 RKE module is part of the door lock Passenger Door Module and the '99 RKE module is in the mini dome light or overhead console and is probably a totally different module.

I'd have to check to see if the '98 RKE module is in the PDM or in the mini dome light. I'll see what I can find.

CCKen

"I'd have to check to see if the '98 RKE module is in the PDM or in the mini dome light. I'll see what I can find."

I looked up the '98 RKE, and found that it is in the mini dome light/O/H Console like the '99.

The parts catalog lists the RKE as a "Keyless Entry Package"

The part numbers for the '97, '98, and '99 are different only in the last three letters of the part number, which in this case makes a difference I would say.

'97 = 5003 378AA
'98 = 5003 378AB
'99 = 5003 378AC

Off hand, I'd say you're stuck getting a '97 PCM.

Try ebay.

Twisties

Thanks for the quick answers!

Just checked, the PCM in the XJ is a 492AE. Sounds like that's a 99, not sure what the alpha suffixes mean.

I had previously checked in the dome, there is indeed a board in there, I had assumed from reading here on the forum that it was for the RKE. Sounds like that's not the case and it's in the door module? If so, what's the board in the dome for?

Thanks again for the help!

CCKen

Can you take a photo of the board in the dome light and post it here?

CCKen

Open this link for a view of the 1999 RKE Module. Pic #4.

Click the image to make it larger.

https://picasaweb.google.com/ken384/...eat=directlink

Twisties

Sure!

Twisties

The number printed on the loose sticker inside the dome is 5FT14RC3.

Twisties

Certainly looks similar.

Edit: And just for grins double checked the build date on the VIN sticker. 4/97.

CCKen

It does look similar, except the wire colors going to it.

Your build date may have started picking up 1998 parts. My build date is 4/99 and it has lots of 2000 parts in it.

Re-reading the '97 FSM about the door locks, PDM and the RKE, it doesn't specially state that the RKE module is in the PDM, it only says that the PDM interfaces with the RKE module.

CCKen

Here's the Overhead Module pinouts for the 97, 98, and 99.

The FSM wiring diagrams do not call it the RKE Module, but you can see the RKE functions in the pinouts.

Odd that the '99 piv cav 2 is called Fused B(+) where the other years call it Courtesy Lamps Feed. The circuit ID's and wire colors are the same for all three years.

Based on this, I think the RKE module you have is the same for the 98 as well as the 99....connector pin wise. Maybe there's something on the board that's different.

Maybe there is something in the 99 PCM that doesn't play well with your RKE module (?).

I think the dealer uses their DRB III Tool to access the RKE through the CCD Bus. Don't know what their DRB III tool procedures call for.

Twisties

That's what they said, that the DRB could not access the RKE because of something different with the 99PCM. Sounds like I need to find a 277AD PCM. Thanks for the help!

Twisties

So an interesting day. A 1997 popped up in the local JY so I made a visit. Same build date as mine, 4/97, 4.0, auto, 4wd, cruise. PCM was a 277AD so I got it.

Swapped it into mine, started right up, and by some miracle the oil pressure/ check engine light issue I had with the existing ECU was gone! Great! On the downside, the 2000 XJ cruise system I swapped in was no longer working . ( steering wheel, buttons, airbag, clockspring ).

Several questions:

What's the difference between 1997 and a 1999 oil pressure sending circuit?

What's the difference between a 1997 and 1999/2000 cruise control circuit?

Edit: I see now that there's a difference between 97-98 cruise buttons and 99+ buttons. Guess I'll have to find some older ones to get this all to work.....

Twisties

I see now that there's a difference between 97-98 cruise buttons and 99+ buttons. Guess I'll have to find some older ones to get this all to work.....

CCKen

The '97 oil pressure sender should have a two pin connector and the '99 has a three pin connector. The '99 is considered a 'sensor' and the '97 is considered a 'sender'.

The '99 PCM would be looking for the 'sensor signal' which wouldn't come from the '97 sender circuit. No signal = no worky.