Thank you ,
I hope it is an easy fix .
I need to find my multimeter which has not seen the light of day for many years and try to remember how to use it .
Could be the oil on the connector at front of gearbox causing issue .some left over from previous leaking valve covers and more from a recent spill whilst topping up .
I referenced the code getting 3 definitions as follows , scary .
Internal control module memory checksum error.
Transmission control module self - test .
Internal control module memory checksum / EEPROM error .
All 3 definitions are listed as BMW FC 80 but have different P code numbers .