As your bike is a gl1000, you should have started a new topic rather than tagging it on this on the gl1200. Please start a new post as the wiring is different. Put your bike info into the topic line to get an answer quicker and not put confusion into this post on a gl1200.
Your bike has minimal fuses and may not have a dedicated fuse for the fan. I don't have a manual to know the answer for you.
The 1000 doesn't have a fuse to the fan. The Thermal switch or the fan would be suspect. To see if the fan is good, unplug the connector at the thermal switch and short across the connectors inside. With power on, the fan should come on. If it does, the thermal switch is probably bad. That's the most common result. Also check the connector at the top of the fan to ensure it hasn't come loose.