Another alarm horn question, 1995 Johnson 112 non-VRO

What causes the alarm to give the short beep when the ignition switch is turned to ON? I know the alarm sounds as the tan wire becomes ground when the temperature switch gets hot. I can't find anything in the wiring diagrams of the engine or remote control that shows how the alarm gets the momentary ground to sound when the switch is turned ON. My issue is the new to me '95 112 will give a steady alarm when switched ON, sometimes. It will stop on its own sometimes after 10 or 15 secs., sometimes it will stay on for several minutes. Once it goes off after the initial turn-on, it acts normally for the rest of the boating trip, with multiple stop / start cycles. I have tried ohming the engine and control side cables and can't find any shorts, tan wire to ground. The temp switches read open to ground. I've bent, twisted, pulled the cables and done everything I can think of to try to make it happen, but can't cause it. It just does it when it feels like it. I'm thinking if I know what causes the short beep at turn-on, it might point me in the right direction. Maybe the horn itself, ignition switch, is the power pack somehow involved in the alarm at turn-on? This motor has no VRO, only the overheat alarm, very basic. I'm stumped.

Re: Another alarm horn question, 1995 Johnson 112 non-VRO

That horn is electronic, not electric.... the circuitry within the horn causes the horn to give a one second beep when voltage is applied to it via the key "on" scenario.

(Odd Soundings Of Warning Horn)
(J. Reeves)

Should the warning horn beep constantly when the key is turned to the ON position rather than sounding just a short beep as it should, do the following test.

Remove the TAN wire from the horn. If the constant beeping continues, the horn is faulty, in which case replace it. However, on the other hand, if the beeping stops, something has gone wrong with one of the sensor components at the engine, in which case start disconnecting the TAN wires that are connected to the various components (Heat Sensors, VRO, Vacuum Switch if so equipped, Oil Tank). Disconnecting a unit and having the beeping stop...... you've found the faulty component.

NOTE: The small black plastic horn that has a built in black ground wire...... The TAN wire must be attached to the terminal closest to that black wire. Otherwise weird things will happen.

Re: Another alarm horn question, 1995 Johnson 112 non-VRO

There is circuit board in the System Check setup that goes bad, it's a well known issue. Mine did the same thing until the alarm would just stay on. There is no fixing it, I just bypassed the System Check alarm and put in a different one.

Re: Another alarm horn question, 1995 Johnson 112 non-VRO

Thanks, Joe. A circuit within the horn answers my question of what causes it to beep at turn-on. Also explains the seperate ground wire on horn. I'm leaning towards faulty horn, but will double check all you listed to check.
Ondarvr, will file away info about system check for future, this motor doesn't have it. It's a bare bones 112 SPL.
Thanks for the quick replies, I'll post back the results.

Re: Another alarm horn question, 1995 Johnson 112 non-VRO

Does it have a tach? Mine was 98' 90 Spl with the System Check, and it is in the tach.