Well im going out to try it on mine now. Lets hope it works. Will let you know. The PCM has already been replaced and the problem returned in a few days.

 

No good here. still have the same problem

 

Back a few weeks while looking for an answer other than replacing the PCM, there was a hot-wire that feeds the PCM. At times, the wires get heat and aged making the wire inside brittle enough to loose contact. There was a posting that talked about replacing that wire to one of the three connectors and getting the PCM to work again. It's been too long to remember where that went.

 

1999 Dodge ram van. V6, 5.9L w air. I have an electrical problem that is very hard to find. The symptoms are that the engine stalls in idle after gauges in the instrument panel peg out. During one stall, a “no bus” signal was displayed in the odometer window.
The cause of the problem is probably due to overvoltage that came from the alternator. My DVM was showing more than 18 volts at one time during a wigout. We have replaced the alternator with a version that does not need a control signal from the computer, which is meant for a diesel.
After the alternator was replaced, we had the computer rebuilt, replaced the coil, replaced the idle control motor/parts, and replaced the instrument panel. It doesn’t have the overvoltage problem anymore, but the gauges still wig out and it stalls.
I need to check the grounding/mechanical on the PCM housing.

 

It sounds like you're losing ground bonding between the engine and body. When this happens the power looks for alternate paths to follow and the sensor wires are the usual places. This tends to cause voltage spikes through the sensors and you see gauges getting pegged.

 

How do I test for ground fault bedtween engrne and body?

 

Connect a digital meter, one lead to the block and the other lead to the body. The voltage should never be above 0.5 volts.

 

I bought this 2002 dodge ram van a couple weeks ago 1500 5.2 engine. The van has been running fine with no problems i went out this morning to go to work and the van wont start just keeps turning over without engine starting then i noticed the fuel gauge buried on empty and the volts gauge was below 8 volts then the mileage started blinking and said no bus!

So i have it towed to a friends car lot where i bought it and started to troubleshoot! I Googled NO BUS and thankfully found you guys to help me start.

I checked all the fuses and they were all fine and then i noticed no power to the under the hood relays in the engine compartment fuse box no fuel no spark.

I changed the crank shaft sensor as the obd11 scanner told me to and nothing!

I started to wiggle the wire harnesses on the engine and i heard the relays click on then off. It turns out the plugs going to the PCM were the problem then i narrowed it down to the plug to the harness plug on the right side of the PCM if you are in front of engine looking in at the PCM i turn the key and it purrs again it now stalls from time to time so now i have to figure out if its the harness plug or the pins on the PCM and it should fix the problem i hope this helps someone else!!!!!!

 

I just read your reply and was wondering if you had to do any further repairs or did you succeed in your clean up procedure back in 2011.

I am going to check out your suggestions on my 2002 1500 Ram Van with 119k on it. Had it since brand new.

 

an update would be beneficial to all