hi guys got a bmw 525 d coming in next week (depending on if i decide to take it on) with transmission light coming on and gearbox going into fail safe mode codes are 4f81 (ratio monitoring clutch a), and 4f84 (ratio monitoring clutch d ),ive read on the net that this can be down to battery or charging faults and also something to do with the seal in the transmision valve body leaking i also plan on checking or maybe replacing fluid and filter in gearbox i know life time fluid is used but just thinking it could of leaked out dont normally do much on transmission but am keen to fix this as not only do i know the guy but think ill gain a good customer. has anyone had this before or can anyone offer any advice
thanks in advance lee