Cm 870 turbo actuator control module

[Rawze]

Corroded or bad wiring from alternator to starter?.

Bad/corroded wiring from alternator (or starter) to batteries?.

Bad battery disconnect switch?.

The main voltage in the vehicle jumping from 13.6 to 12 (or below) is NOT going to be some turbo wiring, but a power cable issue somewhere.

and if you did not get faults for disconnecting the egr valve, etc... then you have a delete file in it. - Put the latest factory programming back in it and straighten out any faults that come up before trying to find ghost issues with boost, turbo, etc. - For all anyone knows, associated fault(s) very well could have been surpressed by crappy delete programming, making it exponentially more difficult to find an issue.