How to use MVP as passthrough?

[mouth]

Mine is charging now, and I tried to use it as a passthrough, but it won't fire while charging, nor will the display work.
I'm charging it off my iphone adapter with a micro usb cable.
How do these units fire when the button glows (red, yellow, green) all the time until it recharges?
Mine is on green, started charging it from 3.9V capacity.

 

[30+Years]

Mine is charging now, and I tried to use it as a passthrough, but it won't fire while charging, nor will the display work.
I'm charging it off my iphone adapter with a micro usb cable.
How do these units fire when the button glows (red, yellow, green) all the time until it recharges?
Mine is on green, started charging it from 3.9V capacity.

Is it turned on?

 

[Miata GT]

It won't turn on or off while charging. Unplug the cable, turn it on, and try again.

 

[mouth]

It won't turn on or off while charging. Unplug the cable, turn it on, and try again.

Bingo!
I always turn my units off when I recharge them (just a weird habit).
When turned on and charging, it does indeed fire.
But I can only check my resistance and battery voltage once.
Oh well, it does work though!