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Here's my tale of woe. '99 3500 5.9 Cummins A/T--Started out with the the torque converter lock/unlock issue, found the cure purely by accident (pulled the alternator charge line which was lying directly on the alternator away from the alternator, and problem went away for a couple weeks until the line returned to its original position--ah ha!!!). Traced the charge line, and ended up basically doing the W-T Ground Mod, things ran perfectly for about 4 years. I could not believe that crazy ground splice on the port side of the motor--engineer must have been hitting the sauce on that one. Wish I'd found this site back then!!! Forgot to mention, I bought the truck used in 2015 with only 46,000 original miles on it--when I had the tranny rebuilt at 90,000, the tranny guy told me there were some non-OEM parts in the tranny--in other words, someone had been in there trying to fix the torque converter issue thinking it was a transmission problem. This has been a source of great amusement to me, as the original owner sold this great truck because it had an "unfixable" transmission problem (and of course didn't tell me)--so thanks, MM1973, for letting people know about this easy fix even though I had to find it by accident! While on a trip out of Alaska, got a no-charge condition and ended up doing an external regulator fix to get home. Never liked the external regulator, as frequently the voltage would run high (15+). After reading MM1973's article on the fuse, decided to implement it and restore wiring to original condition (with the addition of the 5A fuse)--purchased a used PCM, sent it off to be programmed to my VIN, installed it when it returned. Lo and behold, the voltage was in the low 14s and the vehicle ran great with the exception of Brake and ABS lights (turned out the VIN programming did not take; the ABS module did not like an incorrect VIN!) and an occasional "surge" in RPM. Meanwhile, I sent the original PCM in for repair. A friend rode with me and monitored system voltage on his scanner--there was a very slight "spike" of 0.1V every time the "surge" occurred (could only see it on the graph). Strangely enough, the PCM rebuilder reported there were no problems with the original PCM (I asked them to replace that circuit regardless, which they did, and then tested for heat and vibration). When I received it back and installed it, all was well with the exception of the tranny surge--it seemed to be bad one day, and disappear the next. It was not throwing any codes, at least that my Edge reported. About 2 weeks later, while driving to work (temp was about minus 30), the surge got pretty nasty so I locked out the overdrive to smooth things out. Just before I pulled into work, I pushed the overdrive switch--it didn't shift, and my voltage dropped to 11.9. As I suspected, the 5A fuse had blown. I replaced it with a 7.5A, but still had no charging. I'm guessing the original PCM has acted up again. So I put my backup PCM in and went for a test drive. Voltage was good, and she shifted into overdrive. Problem solved, or so I thought. I turned around to head back to the shop, and got on it a little to ensure things were working properly. Instantly the voltage dropped to 11, and no overdrive. Edge pulled down a P1765, P1682 and P0753. Put the ohmmeter to the dark blue line coming off pin C3 25 to the alternator, have good continuity and no continuity to ground (same with green wire from C2 10). Going to have transmission solenoids and wiring harness replaced this weekend based on transmission guy's previous experience with similar issues. Based on the wiring diagram, it seems it has to be a transmission circuit issue. But I'm still totally baffled as to the origin of the no charge situation--either the PCM rebuilder doesn't know what he's talking about or I've got some real gremlins running around in my truck (he said it tested good, and it worked well for a couple of weeks, but now this--and after I put in the protective fuse). And full disclosure--I'm totally dumb when it comes to understanding automatic transmissions and 12V systems, but I did sleep in a Holiday Inn Express once. Sorry to be so long winded! I'd like to hear other members' ideas on this. I'll report back after the solenoid/harness replacement this weekend. Thanks in advance!