P2121 and P2127 codes

[JaegerWrenching]

I'm having problems with a truck throwing these codes P2121 and P2127 and both the CEL and the red lightening bolt are illuminated. It's had a pedal swapped out recently and the same tech who swapped the pedal at the dealer went over the harness on the trans and said it'd potentially had a rub through issue but he re-wrapped it and it was now fixed. I'm really leaning towards a bad PCM as the wires are not shorted to one another or to ground or power, but again i don't have a ton of experience myself with these trucks to know how often a PCM actually goes bad lol. It will work fine for the first 15-30 minutes after sitting over night before acting up. It's very weird but i think the PCM gets warm and the resistance goes up creating my problem. Anyways has anyone had issues like this if so what was your solution?

[Jim P]

Check where the wires go through the firewall for rubbed through wires and verify voltages from and to throttle sensor. The ECM?s don?t normally ?just fail?.

[JaegerWrenching]

Turns out it was a poor connection on the connector that plugged into the bottom of the fuse panel creating a voltage drop as soon as load was applied. Also found another part of the harness on the passenger side that had rubbed through one wire's insulation shorting out on the stud that's supposed to retain it. Work done that poorly is just pure laziness. This truck is beat hard! It is used to chase balloons so it's been through a lot of dirt, mud, and water, everything is in rough shape.

[Jim P]

Gotta love shotty, lazy workmanship