Hi
i am trying to program a key for a E90 ,it asked me to do the cas firmware ,the car goes dead with that and the original key does not work , i did restore car is back to normal

How can i make a key please help

Which part no. is your cas3 unit?some of them are critical but mostly downgrade work like a sharm..I would try downgrade again with stable voltage and without key in ignition is important.if failed again you can restore to its original state and do manualy with programer..read eeprom from mcu and isn from dme make key from dumps

That is normal on some cars. I have sen it before. Just continue with the new key programming. After the restore everything should work.

I tried firmware downgrade and then key learning atleast 4 times did not work the part no of the cas is 61.35-9147196-01

So, what exactly is a problem?

Hi
i am trying to program a key for a E90 ,it asked me to do the cas firmware ,the car goes dead with that and the original key does not work , i did restore car is back to normal

How can i make a key please help

Its normal to lose ignition after you do cas firmware,you must continue with programming key and after programmed check if key recognized in slot from key learning option 1.
if it shows 'YES' in slot then restore CAS from cas firmware ,everything will be normal after that and new key will work too.

Never had problems before with CAS Firmware. Works flawlessly.

after downgrade . and try and do key learning ,it cannot communicate with cas . if I try and cycle ingnition the steering lock will not open and there is a red steering with a lock signal in cluster

If no communications after cas firmware car in sleep mode,just make hazard lights ON and proceed