Yep, that should be fine.
I just find ebay easier, and im incredibly lazy! Was only £2.25 delivered, and to be honest its easier than trying to find a decent parts store online in the UK that isnt Halfords, and i hate them!
I wasnt sure if i could link to eBay or not so didnt want to post just in case!
Small FYI with the LED on the M2...
I believe (and I will double check when I get home) that the M2 keeps both pins for the LED high and then lights the LED by grounding one with the output of the PIC.
You can always just ignore the LED on a switch like the one I linked, and it is easy to double check your connections with a multimeter before you install it to make sure you understand what is happening at each contact. I have mine wired with a pretty high current limiting resistor (10k I think) in order to match the brightness of the LED to the rest of the red lights in the car. However, mine is just wired with the anode (+ terminal) of the LED connected to the side of the switch that is not permanently wired to +12V. When the switch is on the LED is on, and when it's off the LED is off... Simple enough.
I just realized that first comment might be confusing... the M2 can flash an LED. I am planning on eventually connecting the LED output of the M2 to my ACC switch LED so I can see it in the front of the car, so it is useful information if you ever wanted to do something similar...
I get why you'd think you'd want this, however, and again this might just be me personally, but..
Why not simply run a parallel line off the shutdown leads going to the MB so you can manually turn it on/off in that manner with a momentary SPST button, the same as you'd have on your desktop/laptop computer?
I can't speak for this PSU, but there have been instances where I switched too fast between ACC and off and the PSU's controller didn't sense things correctly, so it didn't turn on; things like this are very infrequent, but they do happen. So [to me] at least you'd probably want this at some point anyhow, even if it's not visible.
Not really like Oldspark's in-depth detailed electronic theory really. Keeping in mind your aversion to soldering; you would just essentially cut the motherboard shutdown leads at some length, and attach a second line off of each lead, twist the two together and use a crimp line connector to re-attach it to the PSU single lead for each of the shutdown/start leads. So you still have the PSU's ability to control shutdown/start-up, but also leads going to a button for manual control if you need it.
The PSU still has the power of veto with the microcontroller should it sense an undervolt or the ACC line isn't powered at all. But if it fails for some reason, or you just don't want it to fully power back up, you can just push the button or hold it on for 5 seconds to force it off, the same as you would for a laptop/desktop.
It actually kinda surprises me that none I've seen that are sold for the express purpose of powering a mobile computer (boat, car or whatever) don't already have something like a dual-tap for this built-on. *shrug*
viewed the manual for the M2 from mini-box, it has J9 which is in parallel with J8, which is for the shutdown leads. So this one actually has it all set to go for you, no splicing required. Of course you need to provide the other 2pin connector line yourself, but..
Yep, the 2 pin small plastic tap that goes to the motherboard, usually red and black for the wire colors.
It has an external LED tap as well should you wish to use it, J5.
Here's the manual from the mp3car store, as I think you bought yours from here, right? I assume the 2 are essentially the same, but just in case the firmware revisions are different or they changed some hardware..Basic jumper layout is the same as far as I can tell. *shrug* Don't really care much for this "HV" version..doesn't have the ability from the power settings jumpers to operate past 30 seconds after ACC is cut without disabling the hard-cutoff. Kinda cheese that it doesn't have 10 and/or 15min settings like the other.
Funny that that was mentioned... I read this thread but didn't bother reviewing the modes etc.
But I had a feeling my usual old tricks would work.... (eg, a relay energised by push-button ACC or IGN or alternator charge that could latch/stay on until some other signal or button or loss of the turn-on signal - but you guys know those simple relay plus switch or diode circuits...).
BTW - yet again I agree with Wayne's perceptive comments on how things should or could work, and what is lacking....
(That's without any in-depth analysis, and (LOL!) after resolving hypotheticals related to melted cables thru bad connections.)