Replaced Warning Horn - Now Constant Tone

[Brew2]

1986 Evinrude 140<br /><br />Warning horn was dead (it shorted right at the horn due to exposed wire). Replaced with appropriate OEM horn. Now I get a constant tone everytime I turn the key to the on position. <br /><br />At first I thought maybe something was grounding out in the control box, but I don't think that anymore because I tried testing the horn with the control box split open and made sure nothing was touching the wire connectors...same result...constant tone.<br /><br />Any ideas on where I should start?<br /><br />Thanks.

 

[ob]

Re: Replaced Warning Horn - Now Constant Tone

Make sure the temp sensors or their tan leads are not grounded.That's what is suppose to initiate the overheat alarm.

 

[Joe Reeves]

Re: Replaced Warning Horn - Now Constant Tone

Along with being in agreement with OB, I might add:<br /><br />(Warning Horn Wire Routing)<br />(J. Reeves)<br /> <br />The three wire plastic warning horn that came into existence with the VRO era must have the wires connected in one manner only. To have them reversed results in having the horn omit erratic false warnings. Notice that the horn has two plug on type terminals and one black wire that is incorporated within the horn. The "TAN" (sensor) wire must be connected to the terminal closest to that black wire..... with the "PURPLE" (12v) wire connected to the terminal fartherest away from that black wire.

 

[Brew2]

Re: Replaced Warning Horn - Now Constant Tone

Thanks guys.<br /><br />I checked both the temp sensors and neither is grounded (they both still have that rubber sleeve over the scissor connectors).<br /><br />I'll have a look at where I placed the wires leading to the horn in relation to the black wire tomorrow. I know I have the wires placed correctly per the instructions because that was the first thing I checked when I got the constant tone.... the purple wires were attached to the terminal noted as "+", with the tan wire attached to the other. Not sure until I look tomorrow which terminal was closer to the black wire (presumably it is the tan one...either that or the instructions were wrong). I'll post tomorrow re the wires. <br /><br />Assuming I have the wires connected to the horn terminals correctly, I guess my problem would be the tan wire grounding somewhere. Any advice on how I would go about tracking down where the tan wire is grounding out?<br /><br />Thanks.

 

[ob]

Re: Replaced Warning Horn - Now Constant Tone

Start by disconnecting the tan leads from the temp sensor/s and see if the alarm quits.That is,after you confirm the horn wiring as per Joe Reeves instruction.

 

[Brew2]

Re: Replaced Warning Horn - Now Constant Tone

Forgot to mention...I tried removing tan wire from the horn terminal while the horn was sounding....the horn stopped.... so I assume that means the the horn is working properly (ie. my problem is not at the horn, but somewhere in the wiring leading back to the temp sensors, fuel pump or VRO tank). Would that be a correct assumption?<br /><br /><br />Thanks again.

 

[Brew2]

Re: Replaced Warning Horn - Now Constant Tone

Wow...you type fast ob.<br /><br />I'll try disconnecting at the temp sensors and report back.<br /><br />Thanks.

 

[ob]

Re: Replaced Warning Horn - Now Constant Tone

The overheat is the only alarm on your year model engine that should trigger a steady or constant tone.Sure wouldn't hurt to check the other sensor leads though once you have ruled out the temp sensors and horn wires.

 

[seahorse5]

Re: Replaced Warning Horn - Now Constant Tone

A common problem, assuming that there is no shorted tan sensor wires, is the electronics in the oil tank pickup assembly. Trace the wires from the oil tank to the motor and disconnect them. Chances are they were making the warning horn sound constantly.

 

[Brew2]

Re: Replaced Warning Horn - Now Constant Tone

Bang on seahorse....Tried disconnecting each of the temp sensors with no change to horn. Followed the wires from the VRO tank to the engine, disconnected them and the horn stopped.<br /><br />Went back and grouned the wires from the temp sensors and the horn sounded. <br /><br />Looks like my oil tank pickup electronics have gone goofy.<br /><br />Thanks for the help ob, joe and seahorse. Much appreciated.

 

[ob]

Re: Replaced Warning Horn - Now Constant Tone

Glad you've got it pinpointed down Brew2.And good call on the oil reservoir circuit as being a potential cause of this steady tone alarm seahorse. Seems myself and Brew2 just learned something.