Trash Compactor: Why wont my trash compactor's ram go down?

A faulty drawer tilt switch will prevent the ram from going down more than an inch or two. If the motor starts and the ram moves down slightly then reverses and move back to its top position and the drawer is fully closed, check for continuity through the drawer tilt switch. The drawer tilt switch should only reverse the drawer if it detects that the drawer popped open during trash compaction.

Using a multimeter, check for continuity through the drawer tilt switch with its plunger pushed in. If the meter measures continuity, replace the drawer tilt switch because it's reversing the ram even though the drawer is fully shut.