[striderg3]

After replacing a completely dead battery, the MMI screen will not work.
Car was not connected to a battery tender and sat for many months.
No logo, nothing. Tried pressing down the power button.
Does replacing the battery have something to do with this?
Is there a "hard reset" for the MMI screen?
Fuse maybe?

 

[Mike A]

I would doubt a fuse unless it was having issues before. Put it on the tender and make sure it is fully charged. The new battery could not have enough power to run all components. Let it charge on tender for a day and re check.

Mike

 

[Dmodeejay]

After replacing a completely dead battery, the MMI screen will not work.
Car was not connected to a battery tender and sat for many months.
No logo, nothing. Tried pressing down the power button.
Does replacing the battery have something to do with this?
Is there a "hard reset" for the MMI screen?
Fuse maybe?

I
Im having the same issue how did you resolve this?

 

[Ravill]

I bet your supercapacitor has become discharged. I have no idea how long it would take to recharge it. I'm sure if you left the car on a combo automatic battery tender/charger, it would eventually charge the capacitor.

Someone has also mentioned that there is a lithium ion battery somewhere that powers stuff, so who knows..... Dealer time?