I would definitely verify power in and out of the switch with a voltmeter or probe before changing it out unless you have a spare to plug in just for kicks.
If you've already checked the possibility that you may have knocked a connector off replacing one of your gauges, it's time to take a voltmeter and stick it along the circuit path to verify power.
Even though the indicator light in the speedo goes on with the switch, verify power first to the fan then go forward or backward from there depending on if there is or not. The circuit is not very complicated but finding the correct wire is the challenge.
Good luck
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