Had a few threads awhile ago about transmission problems. I got the new heavy duty rebuild in, new up pipes, turbo (KC stage 1), rear hpop rail plugs, flex plate, all new intercooler boots, etc.

At first I didn't have a 2-3 shift, turned out the solenoid pack was bad, but this took a lot of sleuthing to figure out. I assumed it was a problem truck side and changed out everything that was a piece of that equation, though in the end it was a bad new shift solenoid. Had that part warrantied, put it in yesterday, and everything is good now, truck's running great. What has me still.concerned however is that the solenoid pack I pulled appears to work when I bench test it, though truck is shifting through all gears after install, so I'm driving it....

But, I'm getting a couple of codes and am wondering if anyone else has figured these out.

First one that keeps coming back is P0603 power interruption on KAPWR. This code comes back every time I clear codes, and the batteries have not been disconnected when it comes back. I know the PCM is not causing this code, as it's shown up with two different PCMs. Just having a hydra installed would not cause this code would it?

I'm also getting an exhaust pressure control valve malfunction, P0475. I did put in a EBPV delete pedestal and I put in the Riff Raff EBP isolator pigtail. I assumed this would prevent the code. Was I mistaken and is this code just a part of a deleted pedestal?