Stalling, "No Bus", Crank but no fire HELP

bassslayer25 · Jan 17, 2017

Gonna try and make this as simple as possible.

Couple days ago truck stalled on me pulling into gas station. Started right back up and went home. A day later, while in town, truck stalled out again. Same thing, all lights and stereo worked but I got a "no bus" code along with CEL.

Get it towed home and start trouble shooting. I replaced the coolant temp sensor this past saturday and it started up afterwards. Took it for a test drive then it stalled maybe 5 mins later and I got the "no bus" code again. My brother towed me home and it hasnt started every since.

Since then I have went to a salvage yard and got a new PCM and that didnt solve the issue either. My dad has an 01 Ram with the same engine so I took his PCM out and plugged it into mine and nothing changed again. So that leaves me to believe that its not the PCM? Am I correct on that?

*I guess I should mention that any time I turn the key into the on position the ASD relay starts clicking rapidly.

So I just got done replacing the Crankshaft position sensor and still nothing has changed. Thinking about replacing the ignition coil now.

However, before I do that does anyone have any input on what the hell this could be? This has been, by far, the most frustrating problem the truck has given me. Thanks in advance.

SportRam00 · Jan 18, 2017

Its could be your ASD relay is bad. Try switching it with the ABS relay to see if the truck starts. It could also be a short or a bad ground somewhere in your system. Verify all of your grounds are good from the PCM plugs. Also make sure you don't' have any bare wires inside your wire harness, especially near your PCM plugs and make sure there is enough "slack" in your wire harness near the PCM plugs. If they are too tight, the pins in your PCM connections can pull out slightly and lose contact with the PCM itself.

Find a wiring diagram and a voltage tester and probe all of your sensor signal wires and grounds at the PCM. I tried searching around to find the actual procedure, but you test all the sensor signal wires for their proper signal voltage with the key in the "ON" position. You should be able to find the information for this procedure out on Google. Just search for dodge ram no bus.

dudeman2009 · Jan 18, 2017

Just an addition to the last post. If you are going to test for voltage on any signal wires on the PCM, dont use anything but a digital multimeter with at least 1Mohm impedance. If you use an old analogue meter or test light, you could cause permanent damage.

Yeret · Jan 19, 2017

By chance, does the "no bus" still appear with a different computer? No bus means that there is a breakdown in communication between the ECU and the gauge cluster which can be caused by a myriad of different things. If this occurs with a no-start condition, it usually means an issue with the ECU. In your case however, a different computer didn't fix the problem.

It might be a long shot, but have you checked the main power plug to the power distribution center? I've read that several people that have had your problem had the plug loosen itself from the PDC and simply tightening it down fixed it. The plug in question is the big, square thing with a big bolt in the middle of it. It's in the upper right in this picture...

Stalling, "No Bus", Crank but no fire HELP

bassslayer25

Senior Member

SportRam00

Senior Member

dudeman2009

Senior Member

Yeret

The Village Drunk

Similar threads

Latest posts

Staff online

Members online

Forum statistics

Share this page