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mavdog32
December 24th, 2009, 09:33 AM
Ok I have a full PC in my garage and planned on using it for my tuning but now that I read the dont use external power supply riff raff I am a little afraid to use it. Will I have issues or fry anything?

I got my wife a laptop for xmas :secret: but that does me no good until tomorrow and I am feigning to mess with this thing.

mavdog32
December 24th, 2009, 09:35 AM
er truck info in sig if it matters

mr.prick
December 24th, 2009, 10:45 AM
I think the "external power supply riff raff" is only in regards to
using a DC to AC power inverter.

Mr. P.
December 24th, 2009, 11:35 AM
I *think* the warning was not to power the laptop/PC from the vehicle's electrical system; i.e. if you use a laptop running on battery you're ok, or if you use a PC/laptop plugged into your house you're ok, but the situation to avoid is what Mr. Prick said, plugging your laptop into the cigarette lighter (DC adapter) or using a DC-AC power inverter.

Another idea - after you get the truck driveable, use black box logging and examine the logs & make tuning changes out of the vehicle at your PC. I wish the V2 supported "black box flashing" that would be f'n awesome! But for now you need to flash using a PC.

Mr. P. :)

joecar
December 24th, 2009, 11:50 AM
The problem occurs when multiple ground paths are present... each ground point may be at a different voltage wrt to earth, this causes large currents to flow between the grounds resulting in fried cables/electronics...

e.g. PC/laptop is powered from vehicle battery (non-isolating inverter provides the first ground path) and FlashScan connects PC to vehicle (provides second ground path)... if inverter does not isolate, then current flows between grounds... if inverter isolates it's input and output grounds, then the output ground "floats" and will not flow any current when tied to vehicle ground via PC-to-FlashScn-to-vehicle connection.

e.g. PC/laptop is powered by wall outlet, vehicle battery is connected to charger which is connected to wall outlet, FlashScan connects PC to vehicle... this is more complex and may too have multiple ground paths.

joecar
December 24th, 2009, 11:52 AM
BBF is being worked on.

mavdog32
December 24th, 2009, 12:28 PM
call me an idiot if i am not following but it seems as if you are saying as long as I dont have a charger hooked to the battery in the truck that Ill be fine?

It seems as though you just cant have similar ground sources

Mr. P.
December 24th, 2009, 02:07 PM
bbf is being worked on.

awesome!

joecar
December 24th, 2009, 03:07 PM
call me an idiot if i am not following but it seems as if you are saying as long as I dont have a charger hooked to the battery in the truck that Ill be fine?

It seems as though you just cant have similar ground sourcesCorrect...

Avoid any power/ground connections directly between the Laptop and the vehicle...

Let FlashScan be the only link between laptop and vehicle.

Manbearpig
January 11th, 2010, 09:29 PM
Sorry for the bumpage, but if I have my laptop plugged into a wall outlet could I still flash or will that mess it up? Just making sure. :)

My laptops battery is totally dead.

joecar
January 11th, 2010, 10:11 PM
Sorry for the bumpage, but if I have my laptop plugged into a wall outlet could I still flash or will that mess it up? Just making sure. :)

My laptops battery is totally dead.As long as you're not also charging your car's battery from the wall outlet...

(i.e. in effect connecting car's power/ground to laptop's power/ground).

Manbearpig
January 11th, 2010, 11:04 PM
Awesome thanks!