Arlo Pro 2 power drain at night with DIY solar panel mod

[Dave115]

I had some leftover Pro3 solar panels that worked fine with Pro3 cameras.  I no longer have the Pro3 cameras so I decided to modify them for the Pro2.  I started by cutting off the magnetic adapter and found only 2 wires.  So I took a micro USB plug and put the positive on pin 1 and negative on pin 5, this is the standard charging configuration for a micro USB.  Also put a 1A 50V (1N4001) blocking diode on the positive side to prevent feeding back into the panel.

Setup the panel and camera in full sun, app showed it was charging.  After a few hours the battery went from 60% to 63% at the end of the day I think I had 67%.  I was happy thinking this was going to work until the next morning when my battery was at 40%.  Had very few motion activations so that was not the problem.

Anybody know what's going on, do I need another pin with voltage hooked up?  I know pro3 has 2 positive pins and one ground but I don't have a pro2 panel to check voltages.