If your icemaker doesn't have a button (that another poster mentioned) that will make it go through the entire cycle, then you'll have to use a jumper wire and do it manually. Google your icemaker module. You'll find instruction sheets on which holes (in front of your icemaker) to insert the jumper wire. Your icemaker will then go through a complete cycle of heating up, ejecting ice, and filling up with water (this is when you'll know if the solenoid valve is working).
There's also another pair of holes you can insert the jumper wire into that will turn on just the solenoid valve. Sorry for all the "holes" and if they're vague but I don't remember all the hole labels off the top of my head. I remember one pairing is T-H and that's for the whole cycle, I think. It's been almost a year since I had to do jumper wire poking when I replaced my icemaker.