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Horns - I am stumped

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JPSmit

JPSmit

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The horns on Ms Triss have been less than optimal for a couple of years, so, I finally decided to do something.

I bought a pair of new -much louder - horns and tonight went to install them.

You will recall that a purple wire comes directly from the fuse box to the horn - it comes to the drivers side (LHD) plugs into a spade on the horn and and then continues to the passenger side.

Similarly a purple wire with a black tracer comes into the driver's side and then continues to the passenger side. This wire also continues to the steering wheel where the horn button is the switch and everything is grounded at the steering wheel.

So, I hook up one horn - driver's side - loud as can be.
I hook up one horn passenger side - loud as can be.

I hook up both - nada. well not quite nada - sort of a wants to work noise but not even a fart.

I swap them - individually - lots of noise (both horns work for sure)
I even swap wires - purple from drivers and purple/black from passenger - lots of noise

two horns no noise

I swap the wires on the horn no difference (they don't have polarity do they?)

I check the purple wires - each showing a solid 12.4V
I have continuity in the purple/black wire from the plugs to the horn button

I am pulling my hair out.
any thoughts?
 
Horns draw a lot of amps and need a good ground That ground goes button to the steering rack clean that connection. they do not have polarity. if you still have the old glass fuse it could have poor connection clean same and wire at fuse also. I replaced my old fuse block with new one that takes blade fuses that glow when blown . Madflyer
 
Madflyer said:
Horns draw a lot of amps and need a good ground That ground goes button to the steering rack clean that connection. they do not have polarity. if you still have the old glass fuse it could have poor connection clean same and wire at fuse also. I replaced my old fuse block with new one that takes blade fuses that glow when blown . Madflyer
Click to expand...

Thanks - will attend to the ground - and, I am thinking of going back to a relay. (where is the ground to the steering column?) is it a wire or just the bolts?
 
I would ground each horn. Had to do that before. The ground wire in column usually bolts to dash frame. Look for an all black wire coming from column.
 
JP Run a ground Wire to the bolts for the Steering Column. When things get crudded up and rusty... Normally there is a Relay for the two horn setup. Stock only one horn. I just got a set of trumpet type horns at HF for a very reasonable price. They came with a Relay. If you need info on hte relay wiring I can send over.
 
I would (and did for my Stebel horn) use the horn push to operate a relay and take a wire directly from the battery (thru the relay) to power the horn(s).

My 2¢
 
Pythias said:
I would (and did for my Stebel horn) use the horn push to operate a relay and take a wire directly from the battery (thru the relay) to power the horn(s).

My 2¢
Click to expand...

Thanks all for your input - I think you are spot on in terms of relays and current ( and grounds) - will try to get at it today as long as the garage isn't too hot.


Before I do however, I am trying to determine in my head what gauge wire I should have for the horns.


As I described it earlier the brown wire (heavy - for LBCs) goes to the fuse box, the purple wire (heavyish) goes pretty directly to the horn


I totally understand the value of relays in lowering the strain on the wire harness. (I already use them for the headlights)


However, if I run the same gauge wiring (as the purple wire) from the battery (solenoid) to the horn via the relay, I haven't really changed anything have I? (other than removing the fuse)


So I presume the thing that would change the equation (and allow more current) would be to have a thicker wire.


thoughts? have I missed anything?


thanks for your input!
 
My Stebel horns draw 18 amps. That means 12 gauge wire from the battery to the relay and then on to the horn.

for reverence
16 awg 10 amps
14 awg 15 amps
12 awg 20 amps

I don't know what a single stock horn draws but most of the wiring in our cars is 14 awg which is probably fine for horns as they aren't used continually.
 
Good news tonight, I got the horns working - finally. 12 gauge wire from the solenoid, two relays and bob's your mother's brother.

Next the headlight - bought a new one as the old wasn't working. but the new one didn't work either, dug a little deeper. Of course it wouldn't be as simple as those two disconnected wires now would it? would it? :wall: :grin:
 
Last edited:
JP just like me, Master of the Obvious!! LOL.
 
Jim_Gruber said:
JP just like me, Master of the Obvious!! LOL.
Click to expand...

people regularly say of me that I have a profound grasp of the obvious.

:grin:

Of course I also note that they have not yet begun to plumb the depths of my shallowness.
 
Glad you're not on the horns of a dilemma any longer.
 
Mickey Richaud said:
Glad you're not on the horns of a dilemma any longer.
Click to expand...

Oh definitely still on a horny dilemma :smile: - the signals still aren't working but I decided to work on something else to see if some small victories would motivate me - and they are.
 
we are so easily entertained.
 
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