Air horns will not work

[gerdathome]

Hello!
I have a 1998 Dutch Star on a Freightliner Chassis, Cat diesel engine. I have no working horns, neither electric nor air.I rarely ever use any of them but wanted to call some one to attention the other day when I noticed that neither was working.
I have checked the fuse marked air horn in or under the dash and another fuse marked air horns outside under the front hood and both check out OK. There is also a relay in the inside fuse panel which is designated for the horn.I was not sure how to check if this relay worked so I exchanged it with the fog light relay which was working and found that the Horn relay also worked in the fog light position.This tells me that the relay is working and not the problem.
Next I removed the air horn solenoid and plugged it in to a 12volt connection and it worked as well and opened to let air pressure pass.
I also opened the horn button and found one yellow wire connected to a spring which when pushed or pressed makes contact with a disk. I believe this will only close a ground to activate the electrical horn.
The strange thing I found is that the air horn solenoid has a separate ground connection as well as a wire which should be 12 volt but is dead now.
It seems to be a pretty complicated setup just to blow the horn with two fuses a relay and a separate air horn switch at the top of the instrument panel. I guess this separate switch would cut off the air horn and leave the electric horn active. But right now neither will work no mater how the switches are set
Has any one an idea what I should check next. I suppose a wire diagram would help trace the circuit.
Would appreciate any help or suggestions.
Thanks
Gerry
_________________
1998 Dutch Star DP 3558, 2007 Suzuki Grand Vitara
FMCA 353579

[gerdathome]

Hello!
I have a 1998 Dutch Star on a Freightliner Chassis, Cat diesel engine. I have no working horns, neither electric nor air.I rarely ever use any of them but wanted to call some one to attention the other day when I noticed that neither was working.
I have checked the fuse marked air horn in or under the dash and another fuse marked air horns outside under the front hood and both check out OK. There is also a relay in the inside fuse panel which is designated for the horn.I was not sure how to check if this relay worked so I exchanged it with the fog light relay which was working and found that the Horn relay also worked in the fog light position.This tells me that the relay is working and not the problem.
Next I removed the air horn solenoid and plugged it in to a 12volt connection and it worked as well and opened to let air pressure pass.
I also opened the horn button and found one yellow wire connected to a spring which when pushed or pressed makes contact with a disk. I believe this will only close a ground to activate the electrical horn.
The strange thing I found is that the air horn solenoid has a separate ground connection as well as a wire which should be 12 volt but is dead now.
It seems to be a pretty complicated setup just to blow the horn with two fuses a relay and a separate air horn switch at the top of the instrument panel. I guess this separate switch would cut off the air horn and leave the electric horn active. But right now neither will work no mater how the switches are set
Has any one an idea what I should check next. I suppose a wire diagram would help trace the circuit.
Would appreciate any help or suggestions.
Thanks
Gerry
_________________
1998 Dutch Star DP 3558, 2007 Suzuki Grand Vitara
FMCA 353579

[ET]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">The strange thing I found is that the air horn solenoid has a separate ground connection as well as a wire which should be 12 volt but is dead now. </div></BLOCKQUOTE>

This seems to be your best bet. Have you tried appling 12 volts to see if the air horns activate, hopefully with a fused lead?


My 2002 DSDP has the Air Horn on the same circuit as the conventional horn. It's possible yours was modified to by-pass the electric horn with an added switch. Unfortunately you seem to have done all the proper diagnostics.