E34 525i HIgh Speed Aux Fan not running

["Eugene Hoe" <eugene@xxxxxxxxxxx>]

My E34 525i M20 has the problem of getting very hot when the car is stuck in
a traffic jam or stationary on
a hot day. Found out that the aux fan is running only on Low Speed, the High
Speed isn't running when the
temperature goes up. I checked the fan itself and did a bypass to make sure
the high speed is working and
its working fine. So next I checked the sensor attached to the radiator
which basically triggers the High Speed
fan when the temperature reaches a certain level, that's fine too. But yet
the high speed fan doesn't activate when
the temperature goes up.

Anyone got any idea what could be causing this?. I know I can bypass and
enable the high speed fan to run
permanently but that would only shorten the life of the fan. Any ideas would
be appreciated. Tks.

Rgds,
Eugene
E34 525i

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