No ya don't...6 volt horns will work on a straight 12 volts - they are just louder (dang!)

You do need to use a 12 volt horn relay though instead of the 6 volt, and make sure all your grounds from horn bracket to truck body are VERY clean.

Also, the drawing below shows the horn power coming off the Starter Relay. That's the OEM set up. Run yours off the HOT BUS instead and use a 20 amp fuse. Horns are a high draw item.

 

Julie, On your post #14 what is the function of the wire from gen/reg "B" to Hot buss?

 

In post #14 of this thread it shows a wire going from gen/reg "B" to hot buss. What is the function of this wire and since my reg. has I-A-S-F where do i attach it? 289 with altenator and transister REg. Thanks

 

Hi Bob,

Well that's just different letters used for the alternator system instead of the generator system.

You want the power your generator/alternator is producing to power your stuff directly. So, the power that the alternator is producing goes directly to the "HOT BUS." Then if there is a need to charge the battery, the regulator senses that and adds a bit more. That loops through that main power wire past the HOT BUS and Ignition Switch eventually getting to the battery. So basically, the alternator powers everything first, then charges the battery as though it were just another peripheral needing electricity.



It's a "push me" / "pull you" with what is providing power to the truck - alternator or battery. When the alternator is providing it, and charging the battery (providing power to it for it's needs - same as the headlights, etc) that is a charging situation.

But if the alternator fails, and the battery has to provide that power, that is a discharging situation, and the battery will eventually go dead.

So, that wire is what provides electricity directly from the charging source to what needs to be powered (off the hot bus). If you try to wire the truck like a GM (entirely different set up) and wire the power coming from the alternator directly to the battery, then down to the ignition switch, you'll find you will have trouble keeping batteries charged, and battery life will suffer.

 

Thanks for that interesting explanation Julie. Learning a lot about wiring here. Bob

 

Well, as with many subjects, I find that understanding something, as opposed to being able to explain it adequately to someone else who doesn't understand it, are two entirely different matters.

I'm always willing to try, but if I pass something on and it's pure greek, be sure and let me know and I'll try to clear it up!