Hello. I installed a RoadTop Carplay module on my '14 with ML system. I disconnected the neg during install. At first the unit worked ok, then randomly, after a few more minutes eventually stopped working. I tried starting the car but it won't turn, I just hear rattling/chirpping noises like you hear when you accidentally press START while the engine is idling. I decided to uninstall the module and re-install the OEM unit.. Still the car won't start, 2/3 of the screen is blank, warnings on the dash flashing, and I'm getting a prompt to see dealer. Do I need to get the battery jumped? Is my ML stereo also now damaged? Please help. TIA.

 

Quick follow up: Car is good to go after recharging the battery. I just realized how finicky these cars are when it comes to working on anything electronics.

 

How old is the 12V battery? If its more than 4-5 years old its time for a new one.