i know that other people have been looking for this and i found this to work after searching.
Hold back on the direction indicator (high beams) put int and turn key to position I
and flash the high beams four times and the car will chirp indicating learning mode, and the security light on the dash will
light up. press down on the lock or unlock button and car will chirp when accepting the key fob. and it will
chirp twice when exiting learning mode.

 

you forgot to have the trunk and drivers door open. it helps too if you have your left foot on the ground as well.

 

thanks i forgot about those.

 

door open yes boot open is for x300 doest make a differnce on x308 and x350

i like the left foot thing

 

also you need to hold one arm over your head, close your eyes hop on one foot while spinning around and this all needs to be done from the rear seat on the passenger side on the 4th friday of an even numbered month, while the sun is in its highest position.
None of this is true but that kinda seems like what they want you to do.