Electrical issue with 1966 DeVille

[huskertodd]

I recently blew a fuse and realized that that the single fuse handles my convertible top, power windows, power seat and the horn.  The fuse slot simply says "horn".

Do I have a complete wiring harness problem?

[Chuck Swanson]

Do you have the right fuse?  Commonly replaced incorrectly with the wrong fuse.

https://www.ebay.com/itm/12V-ACG-40A-Amp-Glass-Fuse-Clip-Type-Circuit-Breaker-Chevy-Olds-Pontiac-1955-85-/192488697172

Chuck

[David Greenburg]

I’m not real familiar with mid-sixties, but it seems like that is an awful lot of stuff and amps to be on one fuse. I know the earlier years had circuit breakers for the windows.

[bctexas]

Chuck is correct.  The '66 shop manual calls for a 40 amp breaker in that slot, even though it is marked as a 25 amp fuse.  It says: "On cars equipped with power windows and/or power seats, and on convertible styles, the 25 Amp. horn fuse is replaced by a 40 Amp circuit breaker".  My '65 Coupe has power windows and seat and the 40 amp breaker....

Happy Motoring!

[cadillacmike68]

Horn / windows should be a breaker, not a fuse.

Anyone know a good source for these breakers?

[35-709]

NAPA
40 amp
Part #: BK 7823109
Also have other amperage rated circuit breakers

[Chuck Swanson]

Horn / windows should be a breaker, not a fuse.

Anyone know a good source for these breakers?

Yes, listed the source in the eBay link before your post   $14.99...worked in my cars, but you may find others cheaper. In the link they say it's a "Listing is for one new ACG 40A 12 volt resettable fuse block circuit breaker." 
Chuck

[cadillacmike68]

Charles, I didn't notice the link. 

But it looks just like the one in my car.