How to test warning horn in Tohatsu remote control

[w2much]

I am trying to find out why my warning beeper or horn does not sound when I turn on the ignition. I also need it to sound in order to reset the ECU. I opened the Tohatsu OEM control box to gain access to the horn itself to see if I could make it sound. Does it run on a 12 volt signal from the ECU or a different voltage. It has a yellow wire and a red wire . What voltage can I apply to it to test it ? If it does sound when applying the proper voltage I guess I am dealing with other issues but one thing at a time. This is a 2010 remote connected to a 2010 MD90C2 TLDI motor. I appreciate your replies. Thank you.

 

[pvanv]

Yes, it's 12v. Check the nice color schematics in the Factory service manual.

 

[w2much]

I realize my manual is for the MD90B and mine is a MD90C2. I have been spending some study time on the schematics after putting in the new ECU. I wanted to make be certain I was not applying too much power as the yellow wire traces back to the tach and the ECU. I rigged a light bulb to the horn wires which worked as for testing the circuit. The horn was shot and a new one was ordered. I took a buzzer out of and old OMC control box and again rigged it temporarily so that it works also. I needed a buzzer to reset the previously owned ECU and the TPS according to the Reset Procedure chart in the manual. After 5 or 6 tries I accomplished the reset. Now I need to test the TPS as the idle is too high. It is idling at about 950 with the advancer arm in contact with the fully closed stopper position. I may post another on this as I move along. As usual, Thank you for your time and reply. I appreciate them.