Members who have donated towards server costs
Join Date: Aug 2005
Location: Okehampton, southwest England
Take the black connector off of the fan switch on the bottom left corner of the radiator. Find a piece of thin wire and push it into the connector then place the other end of the wire against a good clean earth or the battery negative terminal. If the fan runs then your problem is the radiator switch. If the fan doesn't run then it could be a number of things, the fan itself, one of the fuses, the fan relay (which is sealed inside the fusebox) or maybe even a poor connection at the fan plug or radiator switch. Even though you are not supposed to be able to get into the back of the fusebox, I managed to pry mine apart once to clean up the circuit board & re-solder a couple of connections that had gone bad, after which I sealed up the edges with silicone sealant. Water had somehow managed to get inside & cause some corrosion. Hope this helps.
1991 BMW K1100LT
1980 Suzuki GS1000G