Warning buzzer alternative?

Phishnvdub

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Hi guys, In a previous post about two weeks ago I determined that my warning buzzer in my control box was bad. It's a '90 100xp motor. I was going to order a new one but had my boat in shop to have the impellar done and motor checked out as its a new boat. Turns out I needed a new steering system so I now have a $750 bill from the marina. So for now I was wondering if I could wire a different kind of buzzer or alert device up to the existing wires that go to the original buzzer. The warning buzzer in my control box has a small ground wire and two tabs. One with two purple wires going to it and the other with a brown. If I am able to wire something up, I am curious as to how I would do it with the wires there? I will be ordering a replacement horn in a couple weeks, but didnt want to take boat out without some kind of warning system. I am going to do the thermostats with the money left to put into the motor for now. Not sure how old they are and would like the piece of mind knowing they are new. Any info or suggestions would be really appreciated. Going this afternoon to pick the boat back up. Thanks
 

Phishnvdub

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Re: Warning buzzer alternative?

Also thinking maybe a 12v light bulb if possible. On the wiring, all I would need to know is how the purple and tan wires work together to make the original buzzer sound when there is a problem.
 

matt167

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Re: Warning buzzer alternative?

Radioshack has 12v peizo buzzers for $2-3. That should do the trick for what you need
 

Phishnvdub

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Re: Warning buzzer alternative?

Thanks I will check those out tonight. Any clue how I would wire it in with the existing purple and one tan wire. I know the tan is from the sensors on the motor, just not sure how these work together to activate the horn when there is a problem.
 

matt167

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Re: Warning buzzer alternative?

You will need to get out a DVOM, and set off a fault to test the system. See where you get 12v. All you need is 12v power and ground to make a buzzer buzz. Just find out which wire sets 12v when there is a fault. I bet purple is ground, and tan is hot. Your sensors would be open if there is no problem, circuit closes when there is an issue, causing the alarm. Simple test with a DVOM will sort out that tho.
 

Phishnvdub

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Re: Warning buzzer alternative?

Thanks, I did some reading on wiring the other buzzer in. I think purple is 12v and when a sensor goes off it grounds the tan wire completing the circuit. Just got boat home, but can't get to Radio Shack to get the buzzer till tomorrow to try it out. Maybe if I get time later I will try the theory with a DVOM. Just have to figure out how to trip a sensor to see if that creates a ground. I think I have read somewhere that I just have to ground one of the sensor wires to do it
 

Phishnvdub

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Re: Warning buzzer alternative?

So with ignition turned on I get a constant 12v using the purple wires as power and the tan as a ground. Lol I am confused.
 
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Re: Warning buzzer alternative?

how did you decied the original was bad. Im not 100% sure why the original had 3 wires but i know its something to do with the reason it bleeps when you turn the key. Im wondering if the temp sensor switch is bad and the tan is grounded like it would be on a over heat. Try to remove the tan from the switch at the motor if the alarm stops then maybe the switch is bad (the reason im not realy sure is it depends if the temp sensor is a switch or a resistive sensor if its resistive then you will need a original alarm)
 

Phishnvdub

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Re: Warning buzzer alternative?

I think it's a switch. That's what it's labeled as in the parts diagram. There are two, one in each head. I will follow the wires and unhook them as you suggested this evening and see if that stops the tan wire at the controls from being grounded when ignition is turned on.
 

kjdunne

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Re: Warning buzzer alternative?

Radio Shack does have buzzers that will work, get the one with 1/4" blades on it. The purple wire is +12 volts when the ignition switch is on. Tan wire is from the temp sensors, also tied into the VRO system for low oil tank level warning and VRO pump for no oil at pump warning. Temp sensors are temperature activated switches, open below 165 deg. f, closed to ground above 165 deg. give or take a few on the actual temp. With the RS buzzer, connect the purple to +, tan to - terminals, leave the black off the buzzer. If the buzzer stays on when you turn the key on, engine off, disconnect the tan wires by pulling apart the bullet connectors in the tan wires near the sensors in the heads. If buzzer stops, try the sensors one at a time to determine which is bad and replace. If it stays on with the sensors unplugged, unplug the VRO oil tank wire. I'm not sure what year the VRO pump was tied into the system, but also unplug the wire from the pump. If the buzzer still sounds with all the above unplugged, you have a short in the wiring harness or cable to the remote control shorting the tan wire to a ground. Let us know what you find that fixes it. Look on ebay for a replacement horn, they are expensive from BRP, but don't run without a working alarm. An overheated powerhead is much more expensive to fix!
 

Phishnvdub

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Re: Warning buzzer alternative?

Dude, thanks for the clarification and details on troubleshooting it. Will have to get one tomorrow after work. Last two afternoons have been impossible to get to RS. I definitely don't plan on going out with out a warning system in place. I have a feeling the temp sensors are bad. Visually checking them I can see bare wire coming out of the back of them and they still have the original factory blue paint. Assuming they turn out bad, does the outside water jacket have to come off to install them? I have done so much reading in the last couple weeks I can't remember if I read they just pull out or that outer cover has to come off. Will keep this thread updated as I get this fixed.
 

kjdunne

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Re: Warning buzzer alternative?

The cylinder head cover needs to come off, then pry out the sender, using a small screwdriver. Before you go to that trouble, check for continuity between the tan wire from the sender and an engine ground. If no continuity, it's not the problem. The tan wire becomes ground for the horn when the sender gets hot, or the other VRO sensors close to ground. If the wire insulation is missing, maybe you can recoat it with one of the "liquid electrical tape" type coatings or Scotch Coat.
 

Phishnvdub

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Re: Warning buzzer alternative?

Will check continuity also. I really appreciate the help!
 

Phishnvdub

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Re: Warning buzzer alternative?

Checked switches in the head last night. Not sure how to get my meter to read continuity and couldn't find the manual for it. So I unplugged the bullet connector at the sensors and put the negative probe on it. Then the positive on where the power from the battery connects to the motor. They both registered that way as a ground as I got the voltage from the battery on the tester. So I am assuming they are bad. Next I unplugged the VRO and the views coming from the oil tank. Tan wire in control box is still grounded Doh! Here's my next question....I am planning on deleting the VRO side of the pump which would leave that and the tank wires unplugged. Why couldn't I just hook a new wire up to the new switches when I replace them and run it up to the buzzer? I would rather not start undoing all the electrical tape to try and find where the original wire might be grounding at unless there is a common place this may happen and someone could point me in that direction.
 

Phishnvdub

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Re: Warning buzzer alternative?

Ok update... Got a buzzer from RS hooked up. It's embarrassing, but I screwed up somewhere when I was previously testing all the sensors. Turns out the oil tank wires and the harness for the VRO make the buzzer go off when the ignition is turned on. I tested both separately. The overheat sensors only activate the buzzer when I ground the wire to a head cover bolt or on the block. I could have sworn those sensors were grounded. Anyway is it safe to say they are still good then? That's the warning I am concerned with most. I am going to disconnect the VRO side of the pump tomorrow so the other two don't really matter. Although, I have read about the tank sensor being bad. Is it common for the VRO sensor to have this problem?
 

boobie

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Re: Warning buzzer alternative?

VRO and VRO tank sensors can give you false readings. The temp senders only give you a horn when they ground out due to an overheat.
 

kjdunne

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Sep 22, 2007
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Re: Warning buzzer alternative?

If you're disabling the VRO oil side, then you're good to go. The factory manual's procedure to test the temp alarm wiring and horn is exactly what you have done, ground the tan wires to an engine ground. The VRO pump has a circuit board potted into it and I've not found any info on how to troubleshoot it. Since it's potted in place, there's no way to repair it anyway. I had an oil tank cause my alarm to sound constantly, so I just left it unplugged since the tank was easily visible, and I could see the oil level.
Happy boating!
 
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