Do I have a bad RAMBo 1.4 board?

Ill start by saying that this is my first CNC build, so hopefully Ive made a simple mistake somewhere.

So I received my MPCNC Primo kit about a week ago, Ive got everything assembled but just cant get the board to turn on… no LEDs, nothing.

Obvious thing (to me, aside from wiring) is fuses. The 15A looks fine. The 2 smaller fuses however - one tested with about no resistence on the multimeter, one way above 0. So I figured bad fuse… received replacements today, replaced both fuses, still same behaviour. No LEDs, nothing. Also tested the power supply that came with the kit, its good. If I plug the USB into a PC, I can see the device show up if that matters.

Am I missing something that anyone can tell? I have a couple pics here as well. Thanks!

Im trying to add links to the purchase and location of the two smaller fuses… but cant post links :frowning:

Pic of the build:


Start by unplugging everything8 from the board and testing with power. It the board works, then take a very close look at the pinout for the endstop switch plugs. In particular, you don’t want anything plugged into the ‘+’ pins, and the order is different between the two rows.

If it still does not work, we seen issues with the screw connection to the 12V plug, and we’ve seen instances of a bad power supplies. Reseat the screws on the connector and check for 12V at both the motor connection and the logic connection. Ryan has recommended not using the connector, cutting off the plug and the end of the power supply and directly wiring the power supply to the control board.

Thanks!! The endstop switch plugs were the culprit. I did also have one fuse that needed replacing, so I guess I didnt waste the time for shipping there but MAN I should have posted sooner.

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