Can custom 3 Bar OS cause a P1637 code?

[Billiumss]

I have a 2001 Camaro SS M6 and I'm adding a Huron Speed turbo kit to my car. I have a forged LS2 with a LS3 top end and using the ZR1 3 Bar Map sensor.

I have an issue I'm trying to troubleshoot and need some help.

I upgraded my stock OS to the 3 Bar OS and did a base tune for start up.

I'm now getting the P1637 Generator L code. I'm not sure if it's related to the OS change or not. All was good before the major upgrades.

Has anyone else seen this before? I buzzed out the wire that goes from the PCM to the Alt and all is good, socket (pin) is also good, not pushed in, car only has 20,xxx miles on it.

[5FDP]

Just upgrading OS's shouldn't toss that code.

If you haven't double check all the grounds too, clean them and what not.

[Billiumss]

I wouldn't think the new OS would but you never know... Did some more troubleshooting....

Pins are all good, all grounds are good and connected. Before starting, battery voltage is 12.50, after starting and running, battery voltage is at 11.97.

In the scanner there is a feature to turn the Generator L-Term on or off, its greyed out when engine is running and scanning the car.

I didn't mention this before but I did upgrade my Alt to a Tuff Stuff 8242NC 175 Amp Alternator. So it looks like my brand new ALT out of the box is junk, awesome! NOT.......