My battery drain and then my windshield wipers don't work in my brake pedal is super hard to press the the floor and my car is idling low I have 2006 R350
Hi there India,
We are dealing with several issues here.
Let's try to address these in order.
Brakes. If your brakes are hard, there may an issue with the brake booster. Another possibility is a vacuum leak, which can cause the rough idle as well.
Battery drain is not related to the brakes.
Do you have a scanner or know someone who can scan your car for codes?