doesnt recognize the usb stick.

 

are you sure you have power to the unit? does the blue light by the aux rcas turn on? if you've replaced the module and we know it's not the car, the only thing left are the cables. could be a short in one of the signal cables or no power to the unit.

 

theres both power and ground to the unit. the blue light on the aux rca turns on.

 

Good news,

My Dension 500 finally works. Bmw had to replace both the tcu and m-ask unit. Total cost for the job, $2700. $1000 alone went into diagnostics and labor .
They replaced the tcu first, worked for a day and i had to bring it back and to replace the m-ask unit.
Thanks God i had aftermarket warranty. They warranty has already paid for itself.
They covered everything. my only gripe is that they didnt want to work on the car with my car audio system so i had to completely uninstall everything.
I wanna thank 545felix, Skeeter, and Nixdoof for all the help.