Hello.

My late '88 E30 M3 fan used to cut-in at exactly the point that the dashboard water temp. indicator touched the red.

The other day, myself and a collegue were discussing how awesome it look having just been Zaino'd and the engine was running, as per usual the fan cut in and I drove off at that point as I knew she was getting warm.

I drove off into town and the stop-start traffic caused the temp needle to go hard onto the right as in past the red 9fan didn't come on)  

I had to pull over for half an hour whilst the rush-hour traffic petered-out and then make my way home. I let the car warm-up from cold last night in the drive and sure enough the needle past the usual fan cut-in point with no fan cutting in.

The problem is obvious: tha fan isn't cutting-in... but what if any easy diagnostics can I perform to solve it. does it operate from a separate thermostat? can I check it out?

Thank in advance

Nick (M3 driver who currently fears driving in town)

I had the same thing on mine a while back

check fuse no 18 - 30 amp (high speed fan 99 oC )

also if yours has the 2 spade terminal switch in rad the low speed (91 oC ) fan should be constantly on when the ign is on Fuse no3-15amp

If it has the 3 pin switch in the rad the Low speed comes in at 91 oC then the high speed at 99 oC .

I always thought i only had a high speed fan as the low speed had never worked since i'd bought the car , That turned out to be the fuse also.

Good luck

Andy

Thanks chaps!

Will check it out when I have some light. No time tonight: Dad has gone to the dark side and bought an RS4 which needs a thrashing from me!

I presently have similar problem where the 1st stage fan comes on but the 2nd stage immediately blows fuse.

It has been suggested I check the wiring as wires may be wrong way round i.e. 1st stage to 30amp and 2nd stage to 15amp therefore blows???

Otherwise it may be the fan motor pushing to much charge?? therefore new fan (gulp!!)

any other ideas?? 

Thanks thought chaps: it was the 30 amp fuse, now she's chilling again! (when chilling is necessary of course).

@ H6 SKH

I'm afraid not... But why would that x-wiring ever occur? Perhaps there would be a simple multi-meter test.....? I don't know about electrons, I know about paint...