Air Horn Not Working

If the truck has been sitting for a while, the horn is probably filled up with monkey snot (white, goopy, oily residue from the air system). Keep pulling the cord and it may clear itself out.

 

First you want to make sure you have enough air pressure to the horn.Take the cover off of the control valve.This cover is the one that your air horn cord inserts intnce inside you will see the control valve.Run the truck and build up air pressure.Disconnect the supply line to the control valve and see if there is adequate,constant pressure.If there is reconnect the line making sure to teflon the fitting.Check the control valve and other fittings for leaks.I use dish soap and water in a spray bottle.When checking for leaks make sure you check with the control valve open and closed.Cord down,cord up.Also check the linkage on the control valve where the cord attaches to.It may be bent to far down to supply air to the horn.Once you have determined that there are no leaks and good pressure to the valve check the lines and fittings at the horn.Take the supply line off the horn and have someone pull the cord,check the pressure at the horn.After you have determined that you have good pressure at the the horn and still no sound take the screws off of the rear of the horn and inspect the spring and diaphragm.Replace if needed.You will only need to replace the control valve if you do not get adequate constant air at horn itself.

 

the control valve might be gooped up. Remove and wash. The diaphragm assembly on the horn itself is pretty simple and may just have a little rust in it that can be cleaned with a green pad.

 

my australian hino 8x4 truck's air seeems to confuse me its not working and although the fuse was ok?how do i fix this

 

Probably a clog in the air line feeding it. Build full pressure and just keep pulling on it till she gives away.

 

If you can hear air coming out of the horn itself, you need to take the horn apart and clean it. There is a diaphragm in the back that vibrates and that is what makes the sound you hear. It takes very little crud to mess up the diaphragm.

 

You need to get that fixed. Children all across the country are counting on you for that amusement.

Back when I was a teen and driving for newspapers it was snowing and coming up a freeway ready to merge and it was really coming down.. I was too afraid to slow down or speed up. Didn't know what to do being a noob to driving. Ended up merging on the freeway about 3 feet from a semi behind me. I ended up getting the friendly air horn salute for antics that morning. Only time a semi honked at me.

 

If your air horn doesn’t work, you are still within the law, as long as your electric horn works. All the law says is that you must have a horn.

 

Dude, who cares about the law. He’s in a semi the air horn MUST work. Little horn is no fun.