This is a fuse for the blower motor. The reason your blower is working is most likely because there is a parallel pathway to the blower. In my 260E, there are actually two fuses in parallel, I never quite understood the reason for doing this. Current to the blower can flow thru either of these fuses. The fact that this fuse blew tells me that at one point, the current exceeded 30A and the other fuse survived it and this one did not.

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Saumil S. Patel