My '01 ram 2500 quit starting about a month ago. The ODO threw a 'no bus' and bad PCM codes. I bought a new PCM and had it flashed with my vin. After installing it would crank but not start, it still showed "no bus" and now was throwing codes for a bad instrument cluster. I replaced the instrument cluster, no start with the new PCM. I reinstalled the old PCM and it started, idled and ran. I drove it around the block, no issues. Parked back in my driveway and let it idle another few minutes to charge the battery, and it died. Now it wont start at all, and the instrument cluster doesn't even light up. I'm going to try to start it with the instrument cluster out, but I'm waiting on a buddy to come jump it after work as the battery is now dead. I'm at a real loss as to what the issue could be. Could it be some kind of anti-theft thing? I'm really out of ideas at this point. Any help appreciated.

 

That’s an odd one. Try undoing both battery terminals and then zip tie them together for about 24 hours to properly “discharge” electrical system

this is a “hard reset”

 

"no buss" is a lac of communication, There are a few threads here on the subject you can look threw. You may want to check the connectors on both the pcm and the dash for corrosion bent pins etc..Also may try wiggling the wires coming out the connectors and see if that changes anything.

 

you might check your fuel pump pressure and fuses under the hood that is your main bus