Hi everyone, I am new to this site with a "new" acquisition of a 84 diesel E350 which has the econoline chassis and an aluminum Grumman Olsen 12ft box. It has been sitting for a while and I am going through the electrical getting all the lights to work. All was going well except the front side fender marker lights have no power getting to them. I noticed that the horn button on the steering wheel is broken and as a result the horn does not work. It looks like the wiring to the side markers are in the same loom as the horn and was curious if they may be tied together. I am also looking for a replacement horn button assembly but have found that cruise control models of which mine is not are different. If anyone can point me in the right direction I would appreciate it. Thanks. By the way I have checked the fuses and all look good. Truck was owned by a local Budweiser distributor and had a very good maintenance history.
Randy

 

The wires might run through the same harness, but I'd wager that they have no connection, electrically. You can verify this by looking at the fuse box diagram.

My money is on a broken/disconnected body ground for the marker lights.

Are there wires for the horn hanging out of the steering wheel?

 

When I removed the rubber horn cover there was half the plastic horn button assembly is broken away so yes there is a mess in there. Regarding the ground issue on the side markers I would not be surprised as I found most of my other clearance lights had ground problems associated with electrolysis from steel screws going through aluminum and rusting. Don't know where the front fender markers ground I imagine there is a electrical schematic somewhere. May take the lazy way out and tie them into the front parking/running lights. The diesels have the two big batteries on both sides that I need to remove to see what is going on. I see one of the horn button assemblies on eBay that may solve the horn issue but not sure about the interchangeability among different Ford models. Thanks for your reply!
Randy

 

You can touch the horn wires together, and see if the horns are otherwise functional.