Atomatic sliding door

sliding door on’06 Pontiac Mountainer keeps opening on its own. Replaced a door pad of some sort and then had said pad adjusted ($110) Dealer says must replace parts to the tune of $600! Any suggestions!

My only suggestion is that if it isn’t still under warranty (is the mileage too high?) get it out of the dealer. Find a reputable, local body shop and have then take a look at it.