What's the temperature in the freezer?

I'd say that's close enough. The first step in diagnosing any refrigerator related issue is taking temperatures (like the doctor). Icemakers generally don't function at anything abve 17 degrees. This precludes overfill problems. Take the front cap off the icemaker. Is the face that's exposed brass colored, or is it plastic?

It's the plastic cap on the front of the icemaker. Approximately 5"X6". If your IM sits in the freezer lengthwise , across the freezer compartment, the endcap is on the left side. If it's mounted along the left wall, the cap faces you.

No. just pop the cap off.

Pull the cap off (it's on the left). You may want to un do the screws that hold the IM in place and turn it so that you can access the face better. Make a jumper out of #12 or #14 gauge electric wire and insert one end into the hole marked, "T" and the other end into the hole marked, "H".

If the icemaker is good it will start a harvest. Remove the jumper when the plastic gear in the center of the faceplate has gone about 1/8 of a revolution. If it continues on its own, the problem is not in the icemaker.

If jumping it doesn't work, replace the icemaker.

I have a manual available for this icemaker and optic operating system. It's too large (PDF) to post on the forum. If you're interested, I will email it to you.

NOTE: To perform the jump test, the door switch has to be held closed, perhaps by taping it down. And the flapper door (on the left of the door jamb) needs to be held down.