Hello Joe37,
Welcome to the forum.
Glad to have you here.
So just to clarify, when you say there is nothing on the digital display, do you also mean that none of the lights are lit up either, IE. the service light at the bottom right corner, or the sleep indicator light at the bottom left corner?
The power plug should be equipped with a GFCI circuit breaker, when you engage it, Red button IIRC, do you hear it "CLICK"?
If not, push the yellow button to trip it, then th red button again to see if it clicks. Note, it takes a firm, solid press, sometimes it doesn't engage and you have to do it again, but don't be rough with it. Do both click, or only one?
It has a flow sensor & won't turn on or run if it is not sensing water, even if there's an air bubble it'll cut power.
Not sure if it will cut the LED display though.
You have to close the plunger valves and bleed the system to remove the cartridge.
Check for blockage in the hoses, skimmer basket in the pool, if equipped with one as well as check the filter itself, unscrew the retaining ring, pull up on the housing, wash it off with a garden hose @ a 45deg. angle to get out all the dirt & debris you can, gently checking in-between the pleats with your fingers. Before reinstalling, check the cartridge housing for blockage at the inlet/outlet.
Make sure your plunger valves are open on the inlet and outlet of the pool and water is entering the unit through the hoses, if not, correct this, then go ahead and open both air release valves, 1-2 turns and then raise/lower hoses until water starts to come out, then close when air stops coming out.
Push & hold the lock/unlock button for 5 seconds, anything on the display? If not, push & hold that same button + the timer button (clock) together for 5 seconds, does the display light up /w "FP" and the pump turn on?
Also, check the flow sensor for dirt/debris/buildup, it's the one in the short section of clear tubing, just before the pump. Unscrew by hand in a counter clockwise direction.
If rinsing it off doesn't get it all, use a toothbrush or other soft bristled nylon brush to clean the hinge and surface, do not use a wire brush.
When done inspecting & cleaning, align the notch on the bottom of the sensor, with the ridge in the housing, turn clockwise to tighten. Do not over tighten, this means just snug by hand, don't "wrench" on it.
Also, you say it is out of warranty?
It has a 2yr. warranty through Intex, did you buy it and it sat this whole time before you finally hooked it up to use it?
It sounds like you only ran it for one day, correct?
What's the condition of your pool, I'm assuming you moved from a dedicated cartridge filter only, the one that came with your pool?