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sprinkles08, Chrysler/Dodge/Jeep master tech
Category: Dodge
Satisfied Customers: 22986
Experience:  ASE Master and Advanced Certified, Chrysler/Dodge/Jeep Master Certified, Trans and Hybrid Specialist
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Hi there, I have a No BUS error flashing in the odometer of

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Hi there, I have a No BUS error flashing in the odometer of my 2001 Dodge Ram Van B1500. All relays and fuses are good and dealer thinks (thinks) it could be the PCM. I can get one for a good price preprogrammed but do not have instructions on installing it. It is the Powertrain Control Module. Dealer states 2 hours to reprogram and $800 for part but I can get it ready to plug in and drive with life warrantee for $199 plus free shipping from PCM-PRO. Can you help me with locating it and any other instructions/schematics to replace the part?

Hi. There is a good chance the pcm is causing this if especially if the van won't start. There are a few other things that will do it too, a sensor or wiring problem can take the pcm down. We can run through a few things if you have a voltmeter to make sure its the pcm if you want.


The pcm is located on the firewall dead center, right above the engine. Its the silver box with theXXXXXconnectors. If you do end up replacing the pcm, don't bother with anything but the aftermarket one with the lifetime warranty. The price is right, and the warranty is far better than the one you'll get on the Chrysler part.

Customer: replied 8 years ago.
Hi there sprinkles, Thank you for this information. You are correct in that the van will not turnover (it does try but gets no gas because of No BUS error. I had tried to find the PCM the other day and was wondering - do you access it from inside the truck dash or from under the hood. Would you say an average Joe can replace it? If it were to be a sensor that is causing the problem, what sensors and where are they located? I might as well check everything as you mentioned?

The pcm is on the outside. Open the hood and look dead center on the front of the firewall and you'll see the silver module with the connectors. To replace it all you have to do is unplug it, pull a few screws out and its off. Nothing to it.


Lets start by pulling the engine cover from inside the van. First find the crank sensor once its off. The crank sensor mounts to the block behind the right head and the end of it goes down into the bellhousing. Unplug this sensor and see if the no bus message goes away and the gauges come back up. If not, find the pigtail coming out of the distributor. Unplug this, go back and see if the bus message goes away. If not, we'll break out the voltmeter for the next steps. If unplugging one of these sensors brings life back, replace it.

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Customer: replied 8 years ago.

Thanks Sprinkles. I have to go get the volmeter, etc. So I can check back with you later. I am going to accept this reply as you have truly given me my money's worth. I will request my next question get answered by you when I return. Thanks so much.

Sounds great. I'll be online for a few more hours here, but I work full time during the day. If you come back during the day and post I'll get back to you just as soon as I can, I do get to check in during the day.


You can accept now if you want, but lets just stay on this same question until we're done. Accepting doesn't cut off communication here, if you open a new one there's a chance someone else may snag it while I'm offline. If you do open a new one make sure to use my name in the question.