90 Silverado 2500 Fuse Marking Question

I have an old beat up 90 K2500 /350. Recently I started troubleshooting my dome light not working and noticed that the lowermost left fuse is marked "CRK" has a fuse in it but no power to either side. I doubt it has anything to do with lighting but wonder what the fuse is supposed to be doing. The only thing I can think of is crankshaft sensor but wouldn't that shut down the engine if it wasn't working?

It probably has voltage applied to it with the engine running.

It probably has voltage applied to it with the engine running.

You have a point there, I should have thought of that myself. Will check it out, thanks.

Fuse no 15 is a crank fuse that may say CRK.

Pull it and see if the starer still works.

Fuse 7 CTSY light powers dome light glove box and radio.