2003 ZX5 Hatchback

When turning on the rear wiper the hatch unlocks (I hear the pop and see the door ajar light come on).

This started almost three months ago. It happened after having a heavy portable air conditioner (for a house) in the trunk/backseat for a few days. It also happened after unscrewing the middle (top) brake light and screwing it back in (was told it wasn't working by the shop, decided to replace it myself, then discovered it's not an easy bulb replacement but requires replacing the entire assembly. On a visual check the right most of the three lights of the middle brake light is still functional.).

I'm not sure whether the portable air conditioner pressing against the rear hatch, or the unscrewing and rescrewing in of the brake light ultimately caused this. According to a person on a UK forum such electrical issues aren't that uncommon with the original UK Focus: https://www.fordownersclub.com/forum...comment=295661

Any instructions or tips on how to fix this without taking it to a shop? Any ideas on what this would cost to fix if I did take it to a shop?

Thanks.

 

I would recommend removing the liftgate trim panel and inspect the wiring harness for visual damage.