Ok, thank you for all the assistance, both in my case here, and for all the great assistance you all have provided for others. It is greatly appreciated

Ok made those continuity checks.

Center pin on the 3 pin jumper has continuity to all V_FANs on all fan connectors
V_IN on the jumper does not have continuity to V_IN on the main connector. I'm guessing we found the culprit.

Now… how do I go about getting that fixed?
I'm 100% certain I didn't short a fan during the install, all fans were prewired with the proper connectors in place, were working before I began swapping over to the Duet WiFi, and are currently working directly off my 12v power supply.

You probably have 12V wired to VIN?

Yes, I have a 12V power supply outputting 13.2V into VIN
V_fan is the jumper I am referring to.
I do not currently have an expansion board.

Always on fan pin sets probed individually
When the jumper is set to the 12V fan (vin fan) position, I get a floating connection (same as dvm leads disconnected) between always on fan + and -. I get 13.2v between vin + and always on fan -. I get 0.636v between always on fan + and vin -.
Continuity checked with power supply disconnected. I get continuity between vin - and always on fan -. Get no continuity between vin + and always on fan +.

In the 5V position, I get 4.9V on the always on fan pins + and -. I get continuity between always on fan - and vin -, and no continuity between always on fan + and vin +/ I did not probe voltage between vin and always on fan pin sets.

I get no continuity between always on fan + and - under either jumper setting.

Can someone please help me with an issue I am having with the DuetWiFi I purchased from Filastruder about a week ago?

I am attempting to get the board up and running properly on an Anet A3 (A single hot end and extruder –for now-- Cartesian printer with a 2020 and 2040 v slot aluminum frame). The issue I am having is with the fans. I have two fans currently on this printer, a 120mm fan that pulls 0.5a, and a 40mm fan that pulls 0.15a, and neither of them run with fan jumper in the 12v fan setting, not even when connected to the always on fan pins. With the fan jumper in the 5.5v setting, I have the 40mm fan running at about 50% (I'm guessing cause it is getting 5.5v). That is not enough to keep the hot end cool, and it non controllable on the PWM fan pins.

I would appreciate any and all assistance in getting this issue resolved.