Holden Ancillary settings

[hoosedamoose]

Hey guys,

I just have a quick question in regards to the tweaking capabilities on some of the older holden models like the VS.
Someone claims that they can change some ancillary settings with a scantool in order to change some transmission and shift parameters over aldl without a chip burner or an NVram.

My question is, is something like this possible at all? it's got me stumped as to how it works. Did GM allow for anything like this to be tweaked? He also claims that theres other settings like thermofan adjustments etc. Is it stored in ram and then lost when the battery is disconnected? This man has changed something in my mates car and the gearbox does seem to go better. But the thing that bugs me is that it has a stock memcal, which cant be written to without a chip burner. It just seems so weird to be able to change something like that over aldl. Any ideas on how it works, if it is true?

[antus]

Not over aldl. You can turn fans on and off wide mode 4 messages for diagnostics, or lock a gear but you cant change shift pressures or fan on temps in the tune. Its either snake oil, or some non pcm hack which may have other side effects.

[Holden202T]

but all the above can be done over aldl if you are using a realtime chip in place of the stock memcal.