Zirgo fan switch

20 amp fuse? Not nearly enough for any OEM fan in the last two decades.

The single fan in the Mk VIII Lincoln draws 42 amps running, and about 55 at spin up. It is fused @ 60 amps.

Electric fan vehicles had 130+ amp alternators in the 1990's. Current large frame Denso hairpins will make 270 amps, to keep up with the bigger fans & electronics. If you plan to use a late model electric fan you will need to upgrade your charging system quite a bit.

Try a 40 amp fuse, since this is your relay rating. Good luck with your project.

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