Bought a powered monitor as it said to do even though I thought it was weird as you usually use a passive monitor with a power amp. Purchased Kustom 10" powered monitor, hooked it up to monitor out....doesn't work. So, called Musician's friend who said "Oh, you never use a powered mixer with a power amp, and sent me a non-powered monitor. That doesn't work either. What do I have to do to get my monitor to work with this system?

On the back panel there is a section labelled Patch Bay
There are 2 small switches which assign each Power Amp to either Monitor or Main Output.
It would seem you have them both set the same at present. Set one to Monitor and one to Main, and use the corresponding Power Amp outputs direct to speakers.

Note you can send signal to external amps or powered speakers from the preamp outputs. This is really handy.
Download and print the manual from https://www.manualslib.com/manual/90516/Kustom-Kpm-8420t.html
and keep it with the mixer.

( Of course don't send speaker outputs to other amps or powered speakers )

Remove the power module from the cabinet. You'll find the fuse on the circuit board.

Remove the power module from the cabinet and you'll find the fuse on the circuit board.

You have two monitor outputs, each controlled by a fader. Plug the amp(s) you will be using to power the monitors into these, connect the monitor speakers to the amp(s) and you're set up and ready

It is a high power rated ceramic, make sure IF you replace it that you use a 5w or higher. Check the resistance to verify with an ohms meter, it should be 160 ohms or close.

In a word, NO. The line out is line level audio... it has NO power amp and cannot drive a non-powered speaker. I have both of these cabinets myself. You need to use an amp with the non-powered speaker. When using an external amp you will need to make sure you phase the two speakers correctely... you could just reverse the speaker leads of the non-powered one if needed.

Hopefully you were powering ALL interconnected equipment from the SAME receptacle. People can destroy the input circuit of powered speakers by plugging them into a receptacle at the stage and then powering the mixer from another receptacle... Pro's know to power ALL interconnected equipment from the same source, be it a receptacle or a power conditioner to avoid ground bounce damage to equipment. They carry power from the stage back to the mixer on an extension cord. You may have had a static discharge that blew one side of the balanced input of the speaker. The parts are inexpensive, however the labor to get at the amp is usually not fun. I have the dual 10 powered Kustom's and one gets at the POWER amp via removing the speaker after the grille... HOWEVER that is to get at the power amp. The Preamp is probably the failure and it is right at the input plug area and you can get at that by removing the panel with the plugs and power switch and volume control.
I don't have the schematic. Look for shorted RF bypass caps on one side of the balanced input circuit and possibly a damaged input op amp.

Have you tried connecting a single speaker to each output and cutting the volume down to see if you have a load or impedance problem? The amp may be perfectly fine except it's trying to play to a 2 ohm or less load :-)

Carl

The outputs are usually just for the front of house speakers - the monitors usually need their own amps.

Check the manual.

You have 1200 watss of power - so keep the volumes REALLY LOW to try things out - otherwise your speakers could be blown by the amp.

You haven't mentioned what model and manufacturer the mixer is. I will have to guess and say that the monitor out on the board isn't providing signal to the powered monitor or the monitor out on your board is powered and is now damaged by plugging a powered monitor into it. Carefully reread your manual and determine if the monitor out on your mixer is powered or line level. Reread also and make sure that the signal you are monitoring is assigned to monitor out, levelled correctly etc. If you find that the monitor out is passive (line level) try hooking it up to an external power amp and speaker. A guitar amp will do for testing purposes. Start with a low input volume on the amp. Also make sure that if it is passive to use a shielded cable from monitor out to input. If your board has powered monitor outs you can use a speaker cable from monitor out to speaker input (non powered monitor speaker).