Today I installed a ebay generic RF remote in my Dads very cherry 1992 735i.
This was interesting because the car is a 7-91 production date and when I opened up the left side kick panel there was the BMW Alpine RF control unit. I had not heard of any prior to 92.
Switched the chip and it works like a charm.Bill-'94 740i
'98 540i
'87 L6