1. I'm not 100% by any mean but the wire and toggle switch on the dash might have been used for an car amplifier turn on wire. Usually though people use the remote wire from the radio. Is the radio stock or aftermarket?
2. The spray nozzles for the fluid are on the wipers arms themselves (i think), if they arn't squirting water then the washer fluid pump probably died. What do you mean by the heater fuse? The wiper fuse I think is the one in the glove box named "wiper" on the top right.
3. The beefy "Power/Ground Battery Cable" Looks too be for a power wire for an amplifier for car audio that previous owner probably took out. Which would explain the tapped wire on the HVAC fuse for the remote wire.
