warning horn 2003 F90 Yamaha

[ncfishhawk]

Sorry mods...not sure how I ended up in the Johnson forum to start with......I'll try again here. Thanks

I have searched the forum for the proper procedure to test the warning horn on my new to me 2003 Yamaha F90 four stroke. It has the top mounted control box on the console, not the side mount type. The horn is under the console, tie wrapped to the ignition switch bracket. I see where I am supposed to disconnect the pink wire from the sending unit and ground to engine but the there is no pink wire on the sending unit?? does the wire change color somewhere in a harness under the cowl? also i assume the key will just need to be in the "on" position, not nessesarily running? thanks in advance

 

[boscoe99]

Re: warning horn 2003 F90 Yamaha

To test the horn, simply pull the kill switch and then try to start the motor. It will crank, but not start, and in most cases turn on the warning horn.

Not sure what you mean by the "sending" unit. The buzzer has a pink wire and a yellow wire. The yellow wire is powered with 12 volts positive power any time the key is turned to the on position. The pink wire to the buzzer is for the ground. With the key switch in the ON position and if the pink wire to the buzzer is grounded the buzzer should sound.

Note that you are only checking the buzzer. You are not checking the alarm system.

 

[ncfishhawk]

Re: warning horn 2003 F90 Yamaha

sending unit i was referring to was the temperature sending unit on engine block. i was expecting to find a pink wire there or somewhere under the cowl.

anyway...no horn when i try it with the kill switch lanyard pulled. i'll look again for the pink wire too.

thanks

 

[boscoe99]

Re: warning horn 2003 F90 Yamaha

A thermoswitch has a pink wire that can be grounded to activate a warning horn.

But, your motor does not have one. Your motor uses a thermosensor. Wire colours are black/yellow and black.

To test the thermosensor warning system, but not the thermosensor itself, disconnect the coupler to the thermosensor. Then, jumper the pins between the two wires with a 220 Ohm resistor. Start the motor. Wait for a minute or so and the horn should sound.

To test the thermosensor you follow the procedure set forth in the appropriate service manual.

I still don't know what the purpose of the test is for. To test the thermosensor, the thermosensor system or the horn itself?

What problem is it that you must be having?

 

[99yam40]

Re: warning horn 2003 F90 Yamaha

From what he has written, I am thinking he just wants to know if the buzzer works

 

[ncfishhawk]

Re: warning horn 2003 F90 Yamaha

i am having no problem, i am just used to getting a test horn beep when i turn the key on my 2 strokes. i'm just trying to see if the horn itself works. i assume it doesn't give the test beep when the key is turned on when starting.


boscoe99, you are dead on right about the wire colors from the switch, sensor or whatever. so is there no way to ground one side of that wiring to set the horn off?

 

[boscoe99]

Re: warning horn 2003 F90 Yamaha

You can ground the horn itself (pink wire from the horn to ground) but not the thermosensor wire. The thermosensor is working on variable resistance, not a connection to ground.

Just go the Radio Shack and get a 220 Ohm resistor and connect it to the two wires. A pack of five is about a buck. That will simulate the thermosensor getting hot enough to activate the over temperature warning system.

 

[ncfishhawk]

Re: warning horn 2003 F90 Yamaha

You can ground the horn itself (pink wire from the horn to ground) but not the thermosensor wire. The thermosensor is working on variable resistance, not a connection to ground.

Just go the Radio Shack and get a 220 Ohm resistor and connect it to the two wires. A pack of five is about a buck. That will simulate the thermosensor getting hot enough to activate the over temperature warning system.

will do. i see several on their website, different watts. does that matter?

 

[boscoe99]

Re: warning horn 2003 F90 Yamaha

No. Watts does not matter. Just get the cheapest resistor they have.