Iím clearly doing something wrong as the device (computer) powers up regardless of the state of Ignition.
If Iíve read the document correctly, the order is:
GND, Ignition, 12V (Depending on which way you look at it, it could be reversed, but same order)
As soon as the 12V connection is made, the device powers on, regardless of the state of Ignition.
Ignition signal does change from 0V to 12V as per key in ignition. (measured)
Device is in P1 mode, ďOn, Off, Off, OffĒ (Down, Up, Up, Up)
ďP1 (recommended): Sends ON pulse to motherboard when ignition is ON for more than
5 seconds, sends OFF pulse to motherboard 5 seconds after ignition is turned off. Waits
another 60 seconds and then shuts down 5VSB to conserve battery. In this mode, the
M4-ATX consumes less than 0.5mA.Ē
As per the manual, itís not supposed to power up the mainboard, until Ignition has changed to 12V for 5 seconds or more. Itís currently on my desk with nothing connected to Ignition, it still powers up when 12V is provided to the 12V connector. A voltmeter confirms Ignition is 0.01V when measured against GND.
For completeness, Iíve not connected anything to the USB port and/or used the software to connect to the unit to configure it. Itís all as per factory with the exception of the DIP switches.
Clearly, Iím not interpreting the manual correctly and Iím getting it wrong. I can supply pictures of input cables and DIP switches if it helps to provide clarify on what Iím doing wrong.
Btw, it was brand new a few months ago, but been a bit slow to build and configure the equipment, and ignored the issue while i was building it on my desk. Now that I'm trying to fit it to the car, its more than a little annoying.