The temp sensor for the OBC is not even inside the car its either in the nearside brake cooling duct or attached to the front panel dependant on the age of your e30.anton wrote:to all those that were confused by:
little fan behind OBC gets noisy..i replace mine. i wasnt smoking something.
just infront of the OBC there is a little "vent" like thingy..
behind this.. i.e part of the OBC(onboard computer) there is a small 30mmx30mm fan. this fan gets noisy and buzzes. i think the fan is used by the obc to draw air for temperature display.
emphasis on "i think"
Anton
I've never seen or heard of a little fan in the area you are talking about

Maybe its something fitted to cars made for warmer climates than ours?