Hi folks. The radiator fan of my B170 is now permanently running, which has been the same for the last week or so. Doesn't matter if engine is cold or hot. I've checked fuses - look OK, I've re-earthed the wires I can see, I've cleaned and WD40'd the large blue fan plug and pushed and prodded other bits. Coolant looks OK although I'll recheck this tonight when I have access to the car. Any ideas? Thanks for any help!