jreynoldsweld

1999 Dodge Ram 3500 DRW. 2wd 24V Cummins. I am getting the no bus, it has happened before and I could clear the codes now I am getting it everytime I start the truck and it will not go away.

I have cleaned everyground under the hood, on the frame and went as far as to put new battery terminals on. Short of ripping into the dash I dont know what else to try. Any suggestions?

jreynoldsweld

Also, the abs, fuel light, and a couple others come on and off with the chime.

torquefan

I would try removing the instrument cluster, cleaning its connections and reinstalling it.

jreynoldsweld

Just tried that. Still nothing. However I took the engine inline cover off blew it out put it back together and it went away for 30 sec....Now its back, wiggle the wires that run into it and it will go away and then come back. I have no idea what do to from this point. Can you even replace that harness/plugs, its got 50 wires running through it....

BigIron70

Check ABS module connector for water intrusion

Mountaineer

p7100 . Problem solved

jreynoldsweld

Why would an injection pump cause a no bus reading? Plus the truck has a fairly new injection pump... Thanks

SIXSLUG

I imagine one or more of the small pins in the connector are not seating against their mate.

Water/moisture intrusion may cause some corrosion also. Lots of vibration there also.

You may be able to tweak each pin just a little to one side to restore a good connection. Just a thought, haven't ever done this myself with the ECM, but have with other connections.

jreynoldsweld

Good thought I will try that.

UPDATE: Just for Edit and giggles, I replaced the altenator. Old one tested good but looked rough. Was probally the factory one. "No bus" message went away, and all lights went away expect check engine light. Test drove: abs and air bag came on once, then went off. All gagues working correctly, but I know its still not right. Tried to clear codes with the same result. Will not clear. Still a little stumped but glad I have my gagues working for now......Any body else ever experence this crap? Thanks

AggieJustin

When it happened on my '01, the fix was to replace the instrument cluster. Not a cheap fix and took forever to get the replacement part.


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torquefan

You've done good. You've zoned right in on the problem area. Now you just need to find out which terminals are for the bus wires, and as mentioned, give each terminal a little tweak to make grip the pin tighter. Often it's pretty easy to remove the terminal from the connector to give it a little squeeze; it's harder though, when there are a lot of wires in the connector. Then give it a good spray with electronic cleaner, blow it dry and add some dielectric grease. It should be good forever. I've made some pin gauges from different sized connector pins, to check terminals for grip; very useful in these situations.
Good luck with the rest of the repair.

Mountaineer

Sorry, after a re-read of your first post I see where your truck is running still. I've seen some no starts with vp failures read no can-bus between ecm and Ip after failure

jreynoldsweld

Still going haywire. Anybody else have any suggestions. The truck is not drivin daily, so it can sit awhile too.

SIXSLUG

Could be ECM goin out.

trust

I went round and round with that problem myself in my 01, there is a TSB and a factory 'fix' available, I tried that, marginal help, tried the new instrument cluster, minimal help, finally after seeking professional help (local mechanic who has a similar truck that I have known for a while) we ended up reinstalling the original gauge cluster but only after looking at every connection and resoldering most of them. It now happens very infrequently and clears at the next restart. Very tedious and annoying to get to this point though and I was very lucky to have someone motivated to figure it out helping me

Good luck brother and if you get it finally really fixed please share, while mine is now a surprise when I get it, I cant say it's truly fixed