Believe me, I can understand. I have seen the stories on here about nightmares at the dealership. Thats why I try to get on here and help folks out. I know how it can be.
As to your question, yes if the cluster is shorted out, you can get the no bus message just as if the PCM was shorted. Thats what makes bus issues so difficult to diagnose, and I have seen some crazy things cause that problem. Unfortunately you are pretty much at their mercy at this point. If I was the one working on this truck, I would probably try to find a truck like yours and swap out the clusters. Or, disconnect the cluster and see if the truck cranks. If it still doesn't crank, then obviously the cluster is not the problem. I say that because in the diagnostic information for a bus failure, it will tell you to disconnect other modules one at a time to see if it has any effect on the bus communication.

 

Another update:

Well strike two on the cluster. Apparently this used one they got wont work either. It's come down to ordering a brand new one at$900. They said they will still honor the original quote of $1200installed forthe new one despite the fact that they have spent about 8 hours labour trying to get the last two used ones to work (I guess I should feel lucky?) They keep telling me that they have ruled everything else out by trying to get these used clusters to work. Does this quote sound about right for a new cluster installed? Any other ideas out there? I just have this horrible feeling that a new cluster is going to arrive and then that's not going to work and I'm going to be hooped. Time was the issue as I stated beforeas I should have been at worklast week which was why I brought the car to dealership in first place. It's been there a week now though, I seem to be no further ahead and am starting to ponder having it towed back home, (about a $60 tow job I suppose.)

 

It sounds like they are trying the clusters and they aren't fixing the problem as they expected. I mean, a cluster for a Dakota is a cluster for a Dakota essentially. I can't say that the cluster isn't the problem, as it very well could be, but I have never seen any vehicle where the cluster caused driveability problems except for the PT Cruiser and thats because the cluster on a cruiser is the BCM.
I would still be leaning in the direction of PCM or wiring, but thats just me. I know how easy it is to fry the PCM in a Chrysler group vehicle.

 

you're most likely getting screwed over, and they're planning to clip you for the full $1200 AND make you feel sorry for them to boot. new clusters are expensive, but used clusters can be purchased from junkyards and ebay from $25-$100, although i don't see that many canadian (km) versions on ebay. i'd go back to their 2nd estimate, around $500-600 when they were talking about fixing it with a used cluster. i'd tell them to either - fix it for that amount, or else put the original parts back on it and give it back - no charge. i'd also tell them to stick the $1200 .....

 

had a no bus cond. on my 99, found it by pushing on the plug to the pcm(center one)

bad conection inside pcm

replaced pcm and been good ever since

cant believe that the cluster would cause a no start cond.

also labour to install a cluster sounds a little high, mabee a 1/2 hour job to replace it, just my 2 cents

 

I don't think they are trying to screw you over, it sounds like they are trying to save you some money by locating a used cluster. Believe it or not sometimes they want to help you. My shop has replaced clusters several times for no bus.

 

Can you have the dealer try something new. They can not talk to the pcm because of the no bus message, Have the dealer unplug the crank sensor and reck, Most people don't know that the crank or cam sensor will take the bus system down causing a no bus message. If the bus comes back online, the engine will start and run not very well, but will run. Also the tps can also take the bus down as well.

 

alot of times a scanner tool can act as the cam and crank sensors if you unplug them. did they try that to see if it ran off the scanner?

 

I have a 1999 dakota had the same problem.I had my cluster disconnected it and didnt make any difference.problem was the pcm.found a internet site where they rebuild yours for about $300.drove truck 7,000 miles since without a problem.now I think I got a transmission problem,but thats a different problem.My truck has 223,000 miles on it so Its been good to me.

 

This would be true for a 3.9 ,5.2and5.9. But on the 4.7 I have seen a crank sensor take down the bus. Same problem happens to the 4.0L jeep, just there is no bus message on the odometer. Just no spark or fuel pump pressure.