Chrysler Repair: 2000 town and country gauges, obd ii, ohmmeter

Question
I have a 2000 T & C LXi.  The Instrument cluster began to lose power intermittently and progressed to cutting out altogether.  I tried changing the ignition switch (the part with the contacts in it) but that didn't help.  I used to be able to turn the key toward the start position while it was running to get the gauges to work so that I could check the gas level etc.  That no longer is the case. I've checked the fuses under the dash and under the hood with an ohmmeter and they all seem good.  I got a known good instrument cluster from the junkyard
but it was a "rev E" and mine was "rev F" the connectors on the back are different.  Are the pinouts the same? I've read several posts related to this and have tried checking the fuses, sprayed contact cleaner in what I believe to be the body computer (two large multipin connectors directly behind the fuses under the dash.

My questions are:
1. Are the clusters interchangeable although the connectors are different?
2. What should I see for voltages etc. at the seven or so wires on the back of the cluster? And since I've had the connector apart many times I'd like to know the correct position of the wires on the connector.
3.Are the data wires on the trans which you spoke of the two on the speed sensor? And am I able to check them at the car end? If so where?
4.Where are the grounding points I should check?

Any help you could give would be GREATLY appreciated since I'm ready to burn this car. (Just kidding)
P.S. The check engine, alarm set, and abs lights stay on. I also had a OBD II readout taken and got a P1698 code if I remember correctly.

Thanks
Al  

Answer
Hi Al,
Sorry to be so slow in getting back to you after my trip. How are things going with the gauge non-function? I have your communication but thought I'd ask first. On the 2.5, I did check and now come to recognize that both data bus wires should have + 2.5V, but they are described as "+" and "-" bus wires for convenience I guess or some other basis. According the to the '98 diagram that other voltage in question is described as present in off/run/start. I am wondering though if the history of the problem, where you described the technique of moving the key past run to near start was a way to get the gauge readings, might not indicate that the ignition switch is the cause of the problem. Unfortunately, the Haynes manual doesn't show the wiring of the ignition switch itself, just the presumed output points and even those are silent as to wire color at the switch so I can't even understand which section of the switch might be bad.
In any case, feel free to write back with a report on where things stand.
Roland


Hi Al,
I am away from home for the weekend, returning Monday late. So until Tuesday I won't be able to check the wiring diagrams and text to give you help. But when I get back I'll send you a reply.
Roland




Hi Al,
My van manual collection is less extensive than is the car manual collection. I unfortunately only have the Haynes manual that cover thru the '99 model year and its wiring diagrams don't show the cluster plug or pin assignements, just the color codes of 5 of the wires to the cluster. The pink wire is a 12V supply from fuse #28 hot at all times, the black/light green is the ground wire that goes to a ground point just in front of the driver side door opening that appears to be about a foot above the floor on the kick panel area, the red/white is a 12V supply from fuse #2 hot in off/run/start position of the ignition switch, the white/black is the CCD data bus wire that should show -2.5V and the violet/brown bus wire should show +2.5V.
The input and output speed sensor wires (red/black and light green/white respectively) of the trans go to the trans controller, which inturn sends the two on a single wire as the vss signal to the powertrain control module on a white/orange wire, then from there the powertrain control module puts that info on the CCD bus wires to the body control module and the instrument cluster. The CCD bus wires are always the colors shown above. The check engine, alarm set and abs lights are on three separate wires going to the cluster and are not part of the CCD bus.
So look for those wire colors to find the data source.
The P1698 code is for "no data bus signal from the trans module". I don't know about the interchangeability of the instrument clusters.
So that is all the info I can give you. I hope it is of some help.
Roland