I have a GPS system I've been using in the '98 Avalon and now wish to transfer to the '05 Prius. The GPS (a Garmin eMap) prefers to have its power always on. Else it goes through a tedious start-up sequence that requires three manual interventions by the driver -- a serious nuisance. The Prius's 12-volt sockets mimic the main power-on swich
In the Avalon I was able to find an always-on 12 volts in a vacant socket in the cabin's fusebox, so no problem. I'm hoping to have equally good luck when I investigate the Prius's cabin fusebox.
My problem with the Prius that that I can't find an available ground point! I'd like to use an easily accessible screw or bolt that's a common ground with other cabin accessories. I've tried ohming between some of the bolts and I can't find any two that are connected electrically. Something's not right. Either my technique is wrong or I haven't found the car's common accessories ground.
I did test my meter and leads; they're fine. (See quotation below. :-)
Is there something odd about the grounds in the Prius? Perhaps isolated busses in honor of the hi-power electrical circuits? Where should I be looking?
And am I due for a disappointment when I test the fusebox's unused sockets for an always-on 12v?
I could buy the shop manual and electrical diagrams as I did with the Avalon, but the Avalon's weren't all that helpful.
Brent "Never trust your instruments." -- Harold "Doc" Edgerton, father of the electronic flash