My son was having fun playing with the horn in my S4. It quit working. I'm pretty sure the 15A fuse blew because now the rear wiper does not park predictably, and these two functions have the same fuse.

My question is, why would tooting the horn blow the fuse? This is a recently installed MOMO steering wheel; is this horn switch somehow a problem?
I am leery of just replacing the fuse without questioning what caused it to blow.

-Sean

 

did you set the turn signal switch height after fitting the new wheel.
To adjust,
Remove the lower column cover,
then loosen the switch,
then slide it away from the wheel hub till the tab is just touching the ring,
tighten the switch

 

First you need to KNOW if the fuse is burned and if it was the right AMP. The horn switch is to supply a ground to the circuit. The L shaped copper strip on the turn signal switch rubs on a circular metal slip ring on the back of a stock steering wheel a wire runs to the horn pad. When pushed down it ground out and you have a complete circuit to the relay. So check the fuse, check the relay and then think about pulling the steering wheel.

 

one thing i forgot to add what was the last thing you fixed?

 

It could be that your horn(motor) is getting old and the resistence is getting high. I have had this happen before and then when you play with the horn to much things get hot andthe fuse blows.
Installing new horns will correct this IF the horn resistance is high.

relace the fuse, disconnect the horns and play around with the horn pad and the wheel to see if it blows the fuse again, but I doupt it unless like was said that your multi-switch it shorting to the horn.

Install some nice old sounding horns as now you have a reason.

Brad

 

High resistance = less current...

As others have said - don't assume - just check the fuse, don't just replace it - check it with a multimeter.

Could be the horn just stopped working for some other reason. Blowing the horn fuse is nothing to do with the switch - but failure to operate (with good fuse) may well be caused by the switch hub connector not installed correctly (or now broken due to turning the wheel...).

Alan

 

You can pull the horn relay and do a little testing at the relay socket with a meter.

The horn ring adjustment is easily done with the ohm meter. Meter probe to relay socket pin 85, other probe to ground. With the horn button depressed, adjust the combo switch position just high enough to get continuity.

Terminal 87 goes to the horns. Resistance to ground needs to be greater than about 1 Ohm (Ohm's Law: 14 Volts/15 fuse Amps) if you expect the fuse to last.

You can put a new fuse in 18, and leave the horn relay out. With the meter set to read DC Volts, put the probes between pins 85 and 86 in the relay socket. Should read battery voltage with horn buttom depressed, no voltage with button up.

Put the relay back in and test the horn. If it functions OK without blowing the fuse, fine. If it still blows the fuse, pull the right front wheelhouse liner, and disconnect the wiring to the two horns there. From that wiring, test resistance to ground. It should be infinite. If there is any continuity to ground, you are chasing a wring problem. If none, you are looking for the horn that has too much current draw. Use your meter on Ohms again to test between each horn terminal and ground. The meter will tell you which one is shorted to ground.


Many drivers discover that the factory horns are less than adequate to warn other drivers in an emergency situation. Options have been discussed here, so I won't list them again. The original horns are also subject to water damage, they break off their brackets or break the brackets themselves. It's worth a periodic inspection just to make sure they are intact, even if they do seem to be working OK. I casually discovered that one horn had fallen from its bracket while replacing a marker bulb. I added a piece of aluminum angle to reinforce the bracket. I should have installed newer-bigger-louder-badder-sounding horns at the same time but didn't. Yet. It's on my list after being crammed by a deaf or well-insulated sleep-driver drifting across my lane. I like the factory horns for casual city-street reminders, but one in a while wish for the truck horn trumpets.

For those who don't remember, a 1957 Renault Dauphine came with a selector switch for city/highway horn volume. Sounds good to me...

 

Oh yeah, I remember. Not really, as I never had a Renault.

OK, going further OT, why was the dimmer switch moved from left floor board to combo switch? I'm sure it was cost saving, but it never made sense to me from a safety standpoint to make it operable by hand even if it was part of an existing operation.

 

Well if the horn fuse was not blown, the rear wiper would still park correctly, so I know the fuse is blown. The horn relay is new, that's the last thing I tried. Then the rear wiper behavior made me realize that the fuse was blown.

Thanks for the tips, I will check the horns thoroughly when replacing the fuse.

-Sean

 

also connect 12v to each horn one of them may have a loose solder joint inside it they can be taken apart then resoldered then readjusted to make a tone

 

I want some Ma-hoo-ga horns

 

Bumping for update,

mechanic told me horns were "waterlogged", and in fact only one was even working, that's why the fuse blew. I got two new horns and it is much better now, sounds more like a normal car instead of the roadrunner.