no horn power

[edekalil]

I have power at the fusebox with a new fuse but no power at horn button at steering wheel?

[banzai510(hainz)]

YOu have brake or tail lights?

 

usually on 510 Im not sure on wagoon if horn is out the brake or tail lights dont work.

 

My fix was the wire under the fuse box was broke. si it looked like it had 12volts on both sides.

But remeber the horn relay has 3 wires and those need to be cked also. I thik the steering wheel puts a ground on there. So ck the wire under by the key also. maybe just needs to be cleaned at the connector

[DanielC]

Power goes to the horn relay, and is applied to one side of the relay coil, and one contact.  When you push the horn button, bar or whatever, the relay coil is grounded, and the power is connected to the contact in the relay that goes to the horn.

 

There should be two thick wires on the horn relay, and one thinner one.  One thick wire will have power, and grounding the thin wire should make the horn honk..

[ggzilla]

I have power at the fusebox with a new fuse but no power at horn button at steering wheel?

No Datsun has power at the horn button. That's normal. Instead the horn button is a ground switch.

[edekalil]

I'll see if there is power to the relay. It more ght be that the horn it self my be bad. I will look at that to. Thanks for the helpfull info.

[edekalil]

Would this be the horn relay? I see it has 4 wires instead of 3. It is attached to a bracket with a bolt through the radiator bracket. Or am I overlooking it. Anyway none of the wires going to this had power.

[ggzilla]

Maybe

 

What car are you working on? What year?

[ggzilla]

For a 510 depending on the year the two relays on the back side of the RH strut tower in front of the fuse box are for the headlights and the horn. The headlight relay has a 6 prong plug, the horn has four individual wires.

 

Other year 510s have a three wire relay apparently

[ggzilla]

Horn failure are not usually power issues unless the fuse is bad

 

More commonly they are relay issues ( bad relay) or switch issued.

 

If you jump the H and B wires on the relay and the horn sounds, it has power. Further if you jump the S wire to ground and it sounds the relay is working correctly.

 

If the relay isn't working right cleaning the wire terminals sometimes fixes it. Otherwise you can take it apart and clean the contact points.

[edekalil]

Thanks for pointing our the location of the horn relay. It was just where you said it would be. I just removed and plugged the wires back and wala I now have a horn.

Thanks ggzilla and all.

[banzai510(hainz)]

that relay you have is a the 2nd contact switch for the points.

 

If you have converted to a matchbox or a pertronix its NOT used or needed.

[ggzilla]

This one on the radiator?

 

Is for dual point distributor? Is used to retard the timing.

 

It is attached to a bracket with a bolt through the radiator bracket....

[edekalil]

Well I have converted my other 3 Datsuns to the matchbox setup.I have one for this car but have not gotten around to converting it. The car still has pionts. I will have to remember that. Thanks again.

[metalmonkey47]

Just FYI, if the turn signal switch is too far down the back of the column, the horn switch will not ground when pressed. Look into that.