Quoted from PoMC:
Modded Grogu and won't work when wired up. Looks like both relays I have are bad because when testing on the multi-meter, I get 12v in, but nothing out on any of the output terminals at all. Grogu moves and powers up when I apply 5v to the motor.
You will need to add a jumper wire from the input terminal to the center (common) terminal of the relay output. It’s not shown in the pdf diagram. Maybe the photo board Joe used was internally connecting those points but the ones linked on Amazon are not. So if you are wiring the grogu power wire to the relay output then you will need to jumper the 12v in to the center of the output. If you are using the relay to switch the ground wire then the center common terminal needs to be jumpered back to the ground input terminal.