How to verify ECU is awake?

I'm pretty sure I've confirmed that my ECU is not powering up. Full system load with either Start or Backup power switches on is only 0.35A, which is likely just the fuse box. If the ECU was on, draw should be closer to 1.5A.

Going to start a new thread to troubleshoot the ECU power.

Pull Off the X3 connector (the one on the Right with 3 heavy pins in it) from The Fuse Box.

Measure The voltage from Pin #3 (The horizontal one on the bottom) to the wire studs on the Ground plate under the "B" Regulator (The one on the Right with the Grey Generator Connector) for ~12volts.

Then measure from Pin#3 to the studs on the Ground plate under the "A" regulator for the same ~12 volts.
If you have voltage on B but not A, you have START POWER but you forgot to connect The A and B Grounds together when applying START POWER.

When all is correct, look in the clear cover of the Fuse Box.
There will be a row of 2 dozen small LEDs next to the Row of Fuses, All illuminated if the ECU is powered up.
They are not very bright and only visible under heavy shade.

I started a new thread about this, assuming that my low amp draw was proof that the ECU is not powering up. But you're saying that my row of lit fuse LEDs indicates that the ECU is powered on? Now I don't know what to think.

Please visit the other thread, see if there's anything we missed, or something not right.