t-train wrote:
Is the bulb burnt out or is the fuse blown?
Most likely YES, in that order, and as someone else pointed out it could be switch failure or dirty contacts.
Procedure.. If you have a test light it is much easier but a volt meter can be used.
Find a good KNOWN ground, if you have to run a wire all the way to the battery NEGATIVE cable and hook the clip of a test lamp to it.
probe both lamp contacts, if one shows 12v (Bright light) and the other is dark, bad bulb, NEITHER shows light, probe both sides of the switch,, IF still no light blown fuse
If light on one side of switch but not the other,, Bad switch.
IF bulb tests bad, Clean contacts and re-test
If switch tests bad, clean contacts and re-test
If cleaning does not fix.. Replace.
If fuse tests bad. replace.