GetUpnGo

I broke the rear wiper arm on my hatchback when I accidentally turned on the rear wiper with the bike rack on my car. It wasn't raining at the time so my front wipers were off. The problem is a switch that's easy to flip on accidentally when I use the turn signal. This has actually happened a few times in the past before the arm finally broke. How can I avoid this in future?

Upon reflection, I think it would be easiest to unbolt the wiper arm each time I put the rack on the car. That would mean a lot of mounting and dismounting the rack as well, because I sometimes leave it on the car when I'm not using it and I do want to have a functioning rear wiper for safety. I don't want to risk breaking the wiper motor in addition to the arm. $$$