How to test alarm buzzer for high temp/oil pressure/lube monitor

[enginesilo]

My boat has a buzzer under the dash, and the wiring for the probes, but does not have them installed. Is there any way to test to see if the wiring is all functional and the buzzer? If I understand correctly the sensors are simply a relay that stays closed and when they reach their alarm point they close and make a connection, is that accurate?

So to test, should that mean that I can take a piece of wire stripped at both ends and enter it into the tan/blue wire, and the black wire that sits near the thermostat where the temperature sensor sits? Would that activate and make the buzzer sound?

Right now when I turn the key the buzzer does not make any noise. I do hear a chirp, but I think that may be my build in depth finder possibly.

I'm considering installing the sensors but I want to confirm everything that is existing is working as is. How can I test it and activate the buzzer?

I have a Searay boat by the way with the 3.0L Mercruiser engine.

 

[dubs283]

if the engine warning horn is working turning the key to the run position before starting should sound the horn (low oil pressure), sometimes the horn takes a bit to turn on, ten seconds or so

to test the other warning switch curcuits, simply ground the sending wire at the switch

if the horn is diconnected, it will never sound

 

[enginesilo]

if the engine warning horn is working turning the key to the run position before starting should sound the horn (low oil pressure), sometimes the horn takes a bit to turn on, ten seconds or so

to test the other warning switch curcuits, simply ground the sending wire at the switch

if the horn is diconnected, it will never sound

My boat is not equipped with any of the actual sensors (Low Oil Pressure, High Temperature, or Low Gear Lube). I can see a buzzer in the zip tied bundle of wires under the dash, and there is wiring near the thermostat and the gear lube for those 2 to get hooked up to (Tan with Blue stripe, and black wires). Right now when I turn the key I hear a quick chirp which may be my depth finder, but there is no buzzer when I turn the key at all, ever. I'm guessing it doesn't buzz because there are no sensors in place.

what do you mean by ground the sending wire? If I have a tan with blue wire, and a black, would I connect the 2 together with a spare piece of wire to close the circuit? I don't have a ton of wiring experience, sorry for the rookie question.

 

[Bt Doctur]

locate the alarm horn under dash, find the tan/blue and see if its connected to the harness wiring. If yes, go to the engine, locate the tan/blue wire and connect it to a ground , alarm should sound

 

[enginesilo]

locate the alarm horn under dash, find the tan/blue and see if its connected to the harness wiring. If yes, go to the engine, locate the tan/blue wire and connect it to a ground , alarm should sound

Thanks for the info. There is a black wire right near the tan/blue, can I use that ground, or should I find a ground on the engine elsewhere?

I did some crawling around under my dash and the buzzer exists, and IS plugged in. When I turn my key, it chirps for a fraction of a second, but that is it. No extended beep or anything like that. Is that common when there are no sensors installed?

 

[dubs283]

is there a gear lube monitor mounted on the engine??

 

[enginesilo]

is there a gear lube monitor mounted on the engine??

No gear lube, thermostat, or oil pressure sensors at all. Just a buzzer, and the wiring.

 

[dubs283]

then your warning horn is useless, unless you install warning horn switches on the engine

 

[enginesilo]

then your warning horn is useless, unless you install warning horn switches on the engine

i can't agree with you more, but the reason for this thread was so I could learn how to test the system to see if I can activate the buzzer to be sure it all works since I am considering adding a few of the sensors. Wanted to be sure it all worked before investing.

 

[pyrotek]

Ground tthe tan/blue wire to test the buzzer. You can use engine ground, battery ground or the black wire. The buzzer had two leads. One side is connected to +12v at all times. Then the other side - the tan/blue wire, needs to connect to ground to complete the circuit and have current flow through the buzzer to sound. Therefore you can put any number of sensors which are just switches on the tan/blue wire to sound the buzzer. All the sensors or switches get put in parallel and any one of them that activates completes the circuit to ground. You can also do continuity test between that black wire and any other terminal you think is ground to confirm its all connected.