do you have a column shifter? if so, i would look in the column and see if there is a simple switch that when the lever is in the park it grounds out the citcuit that allows the dvd to operate. as said above, the after market one require you by law to wire it to the parking brake, however if you put on a grounded toggle switch you can flip the switch and watch to your heats content. i would advise against it tho, unless it's for the passengers only. just my .02 cents