Kicker ZR360 Car Audio Amplifier "speaker cone locked" Questions

...speaker. Don't need a sub, you just want to test the sound. I recently blew 2 subs, no smoke, no smell, no sign of being blown. Absolutely nothing from the subs.... In the past my sub locked up. You ...

...lights are grounded...as well as other things.( I figured it must be a decent ground point) The speakers are 10 inch subs which are mounted on a 1.5 inch thick board, side by side, and that fits ...