Combines 7720IJ

first check the fuses. make sure there is 12v power there. if not remove the cover around the control panel and check for 12v out of the feederhouse botton to the slow shaft speed mon. harness.if power is to both of these check the power mod. box for 12v out of it. on most models it is behind the pannel.

The 7720 does not have a threshing hour meter so there isn't really a way to know.

Separator hours are usually around 70% of key hours in most cases