Easy one for Luke - head unit power question.

[george graves]

It's been ages since I've installed a HU. I have a very generic question.

Head units. All the ones I've seen have two power wires. One gets constant +12v. The other gets switched ACC.

Can I assume the following?

- All decks draw the majority of their current from the constant +12v. The ACC only acts as a switch.
- 95% or more of all factory decks also use the same set up (12 constant, ACC)

[StereoInstaller1]

yes and yes, except "Data Buss" cars....GM, Chrysler, Ford all do nasty things now.

MBZ and BMW have been at it a while now.

[DaveSmed]

As far as the majority goes, I dunno. I DO know that Genital Motors products draw the majority of their headunit power from the switched lead. I think some other stuff does too.