I'm having a very strange problem. I bought a Targus universal auto/air adapter. I am using it to supply regulated 15.3v to the ITPS (since without it, the ITPS won't provide 12 volts to the computer when the engine is off).
It worked at first. Though it seems to only work 10% of the time. The other times the Targus PS makes a "clicking" noise, every 2 seconds, as though it is resetting itself (the PS has protection for temperature, excessive current draw, under voltage), and the computer never turns on. I did see one situation where the computer actually kept rebooting itself, but haven't seen it since.
Again, it works 10% of the time or so, and I can't figure out the right formula that would make it work every time, I don't think there is one. I am getting an OPUS 90W to replace all this stuff, but that will take a while to get here, so I'd appreciate any thoughts people have on why the Targus PS might be failing.
I would have thought it was failing because it is hitting the Targus' 6A limit, but I don't think that's it, since the "clicking" noise occurs even when I have just turned the ignition, before the ITPS would attempt to start the computer (so load should be low). I did measure the draw a week ago, and the computer drew 5.8A max on startup, but again, when the clicking noise occurs, this is before it would have drawn many amps.