warning horn test

[Thumpbass]

Is there a way to test the warning horn in the control box for a '79 Johnson V-4. The control box is not connected to a motor (or power). I have the wiring diagram for the unit if that helps.

 

[ezeke]

Re: warning horn test

If you have the OMC wiring diagram, it should show the Cable connector (Red Plug)

Voltage applied to the tan wire (negative inside 7 0'clock) and purple wire (positive large outside 5 O'clock) should sound the horn.

 

[Thumpbass]

Re: warning horn test

If you have the OMC wiring diagram, it should show the Cable connector (Red Plug)

Voltage applied to the tan wire (negative inside 7 0'clock) and purple wire (positive large outside 5 O'clock) should sound the horn.

so I can just use some test leads and hook them directly to a cranking battery?

 

[ezeke]

Re: warning horn test

The purple wire is the positive lead from the battery. The Tan wire would connect to the temp sensor on the engine, where an overheat would close or ground the circuit and sound the horn.

Any 12 volt DC source should be adequate to sound the horn for a test.

 

[Thumpbass]

Re: warning horn test

thanks, man!

 

[Theoutdoorsman]

Re: warning horn test

Thumpbass........... You MUST remove the temp sensors, and check them with an Ohm meter, to make sure the circuit is closing at the correct temperature in order to determine if the sensor(s) is good or bad. That is the ONLY way to know for sure. Just a little heads up, they will run you about $55 a piece if you have to replace them. Luckily, mine tested good!!!........But definitely check them and make sure they're OK.........Have you decided to rebuild that 140 on your own?............Good luck.................ALAN

 

[Thumpbass]

Re: warning horn test

I probably won't rebuild my old motor (actually a 100hp) if for no other reason I just don't have the time not to mention adequate tools and shop space...plus my mechanical skills are in the early learning phase. I'm leaning towards getting a different motor and keeping my old one to tinker with later on down the road...I don't want to learn on the motor I'm going to have to depend on just yet.

I wanted to test the horn in my control box just to make sure the horn it's self was working...the old motor isn't even on the boat anymore...when I get a replacement, I plan on checking the temp sensors...now that I know for sure that the horn works, I will know when I check the new motor's temp sensors that if I hear no sound, it's the sensor and not the control box that has the malfunction

thanks for the info