Hey guys,

This happenned awhile back once, reset pcm and forgot about it. But today, my dash has been dinging an during lunch while driving.. flashes 'no bus' on the odometer and all the indicators go left (no tach, no speedo, no gas..etc.). It still drove ok, when I got to office I reset pcm and all the stuff came back.. I did the cluster self test and came up with this?

AA 03
Ab 03
Ac 03
Ad 03
AE 03
00 00

I redid the test and the 03's changed to 06's, I did a search on DT and got this:

"Assuming there were no other faults codes found on your scan tool besides the U0155 you can rule out your PCM. The engine keeps running and the transmission doesn’t drop into a second gear limp in so rule out the PCM. The problem is most likely in the instrument cluster. The codes it recorded AA/PCM message not received, AB TCM msg. not rec, AC ABS msg. not rec., AD FCM msg. not rec., AE ACM msg. not rec. The fact that the cluster captured and stored all of these faults indicate that it probably had 12+ volt and a good ground. All of the other modules must be communicating with each other fine or you would have an overall PCI BUS failure fault (lots of crazy problems and a ton of issues if this happened). This points to problem in the instrument cluster processor or the single WH/VT wire or connector that I mentioned in my 1st post. If the problem continues to happen you can order an exchange cluster at your dealerships parts dept. It’s been 10 years since I’ve worked at a dealership but back then exchange clusters ran between $125-200. They would need to scan your truck to get the VIN/PCM mileage/Cluster recorded mileage/engine hours."

Anyone have any ideas?

update for today..

yea randy, I did do the newest crom a couple weeks ago...and then took it off and went back to 3c (but I still had the same symptoms)

But check this out... yesterday I went to Modesto (75 miles one way).... an hour before I left I decided to disconnect battery and reset that way. First 18 minutes, no dings, dash works fine. Then i got 1 ding (Abs), then a 2nd (brake)....I pushed forward and the dings became more frequent...then about 20 miles later the dash starts to act funny (not all at once..but the water temp/oil pressure would go off, then on...then gas/batt would do same thing)....then eventually all the guages go dead with the 'no bus' in the odometer and the engine light on. I decided to let it be until I got to the next city...I figured it was nice not to hear the dings. well, about 15 minutes later as I'm comin into town all the guages started working and only engine light stayed on so I press forward to my destination (about 30 minutes more)...all that time no dings, dash works fine. So, after i finish my work and I'm headin home, guages work, engine light on, no dings. Stopped at SB to get coffee b4 jumpin on freeway. When I go to startup, all guages work, engine light off (Cool!)...get on freeway and drive all the way home with everything working fine. Came to work this morning (25 miles) and all is still fine, no digs, dash works...go figure..

now my guess is that the pcm had to learn because everytime this would happen before I would clear the codes and an reset pcm. This time i let it go, didn't reset codes or battery except yesterday morning... so, do you all think the pcm just learned and adapted? I'm runnin out to san jose now (80 mile round trip)..we'll see how that goes.. will keep you all informed..