As far as refashing the pcm, it's not a common problem but it is a common thing. If there is a problem with different aspects of the vehicle GM will come up with software to correct a problem, it's more of a calibration for the car, thats why there are software updates. Just tell them you found a bulletin outlining your problem and you fixed the ground but need the pcm reflashed. The tsb number will be the same nomatter what country your in. Some other in for I came across is this tsb:Vehicle may crank and not start or may not stay running intermittently.
The 4 bolts that hold the underhood bussed electrical center (UBEC) may become loose, causing a poor connection at the back of the UBEC.
Tighten the 4 bolts that hold the UBEC to the inner fenderwell.
If you go to the dealer they have access to these bulletins.
Sunday, February 4th, 2018 AT 2:40 PM