[smoothdemon]

So you may want to refer to my last post for some history to this question:

http://www.mazda3forums.com/index.php?topic=17231.msg1226465#msg1226465

Anyhow - I decided to go ahead and dual horns to the passenger side of the car and leave the stock horn on the drivers side.



The dual horns I bought ground through the mounting bracket - they won't honk if they aren't grounded. Well i thought i found a good spot to mount them. when laying on the ground looking up on the passengers side near the bumper (after large black plastic cover is removed from under front of car), there is a black bracket with 2 bolts supporting a large silver cylindrical thing (power steering pump?) Well the bracket is covered in paint and the bolt holes on the thing (pump?) have rubber seals.. so my horns wouldn't honk. So i ran a grounding wire from the main passenger side ground on the frame down to both bolts/brackets of my horns. Now they honked and sound awesome by the way...

Anyhow after driving a while, i noticed (especially at a stop or while driving slow) that when i turn the wheels, i hear a loud whine, turn to the left - whine, turn to the right whine. it seems to be getting louder, and i think its the power steering pump?... could the ground be doing this??? is it a bad coincidence? suggestions?

i don't know where else to mount the horns otherwise... :/

 

[MX-5]

The power steering pumps on the 3 are sometimes noisey to begin with, and now your horns are resonating some of that sound because they are solidly attached to the pump. (horns are basically acting as a speaker)

 

[smoothdemon]

after stressing out a lot - i thought about what you said, and it's totally true, the whine is being amplified and projected thru the horn casing - : /

i don't know where else to mount and the whine isn't that bad so i will leave them there... thanks 8)

 

[mz3frs]

Good thinking MX-5...

If you want to mount them elsewhere, you could put a ground wire under one of the horn's mounting bolts (preferably with a star washer) and run it to a ground point on the chassis (or the PS pump bracket even). That way your horns would be grounded and not resonate you're PS pump's whine.

 

[MX-5]

Good call