My 99 Ram the fuel, alt, temp,speedo and tach will quit working and the odometer reads "No Bus" the lights, A/C, radio will still work then the gauges will start working after awhile. What does NoBus code mean? It stays on a few minutes and then the gages start working again.

My '00 Dakota R/T acted like that when the PCM lost a connection inside it. NoBus is a communication error IIRC.

Bus is the communications between the modules.
Could be a single wire that loops around to them all or a pair of twisted ones. What's the code?

If it's doing it all the time that's a good thing Chucko! With a scan tool I like to see what modules I can communicate with, and then start unhooking every module that's on the bus one a time. Sometimes you get lucky and when you unhook the affected module (which can also take some of the associated sensors in the circuit out of the loop) the system will come back up and at least you'll have some direction in which to look.

The "no bus" can also act like windows. You might unhook something, everything starts to work, plug it back in.....and everything still works. That's why this is one of those "hated" issues. You might work on a customer ride for two hours, and suddenly "poof"...everything works.

we had that in an 01 ram, there is the "twisted pair" that runs down from the ip panel tot he main harness, check there to make sure it hasnt rubbed thru, there is a series of diagnostic checks to test the condition if the ip cluster, but it sounds like a comm error either in the pcm or in the wires to the ip cluster

I have seen more problems with "Bus communication errors" in the instrument cluster than anything else and I have never seen one where it was the wire it self. I am not saying it is not the wire but it is pretty rare. BCMs are pretty common failure that can cause that but again not limited to them.

I have a customer that had the "no bus" come in. From a few previous experiences I unhooked his ABS module, went key on, and plugged it back in. To this day it's never gone "no bus" again. Believe that was a 2000 CTD with 4WAL brakes. I've also run into clusters (which is a "module") that have had internal issues. Another one on the gas trucks and some Jeeps with JTEC that could cause alot of grief was the crank shaft sensor could short taking down the BUS.

Not to throw another wrench into this, but my fiance's 2000 Cherokee was reading "No Bus" across the electronic odometer and the gauges wouldn't function. It actually turned out to be the Crankshaft Position Sensor. There is a way to physically test their resistance to see if they are bad, but they are a b*tch to access.

If it is a sensor causing it you can try unplugging the sensors one at a time and see if it will restore comunication, when comunication comes back you will know witch sensor s bad.

I have had internally shorted cam sensors (4.7L engine), crank sensors and A/C transducers cause the NO BUS code.

2weeks ago had the exact problem in my wife's 2000 Ram & we took to my friends shop. One of his mechanics hooked it up to the OBD2 tester and they said the instrument cluster was bad. I got one from a wrecking yard, they installed it & now everything works just fine. Only paid $50 for the used cluster,but remember the mileage will change with the cluster,so if it's important to you make sure you have it documented in case you sell vehicle.

There is alot of problems that can cause NO BUS. Bottom line is you need a tech who knows what he is doing to check it out as J-Body says. If not you can guess and throw parts at it that can cost much more then paying a good tech to fix it. Ron