Hi everybody!
I've just fitted an OBC to my 1992 E34 525i auto.
The unit seems ok, records average speed (which seemed reasonable enough figure for my daily grind to work) but there are no MPG fuel consumption figures displayed. Both Cons1 & 2 remain at 0.0mpg. Tried pressing S/R button again and again but after driving there is still no figure given.
I tried disconnecting the OBC, then recopnnecting so all reading were blank - did a Display test in case this resets anything, or makes the car 'talk' to the OBC, but this had no effect.
The figure for Range looks reasonable too, 1/4 tank, 109 miles.
is there anything obvious here that I'm doing wrong? 
The part number on OBC is 65.81-1389619 and the supplier, and dealer, both assure me is compatable with other units 65 81 1 384 149 and 65 81 8 351 055. One of the functions confirms it is a 5 series unit too (Simultaneously pressing the 100 and 1 displays the car version number).
Cheers
(btw: Outdoor temp seems high too, 10.5c on gauge, only 9c outside but really need a thermometer to prove this one rather than going by the forecast!)
