Continuous warning horn

[BoaterBor]

I have a 1997 Mercury 150 hp EFI with the warning horn on continuously, I changed everything I could think of still have the problem. I 99% sure I have a short somewhere, my question is could there be a short in the ignition switch?

FYI I changed the water temp switch and sensor, water pump impeller,warning horn module and the oil tank low oil quantity sensor that's why I'm thinking a short somewhere

 

[racerone]

Could be the horn itself.

 

[BoaterBor]

It's possible and it's an easy check Thanks

 

[Dukedog]

have you disconnected tha "purple" going to tha oiler module?.. there is also a plastic terminal on starboard side that should have 3 tan/blue or maybe just tan wires made up on it.. one goes into tha harness which goes to tha warning buzzer. one goes to tha over temp sensor.. one goes to tha oiler module.. disconnect one ta time to figure out whats causing tha alarm.. if you disconnect tha one going to tha harness and buzzer goes away it will eliminate tha harness/key stuff of short/bad somewhere..

 

[BoaterBor]

I did disconnect the purple one but not the other three I'll give it a try thanks

 

[Dukedog]

do you have an oem manual for tha motor?

 

[BoaterBor]

I'm look at schematics online

 

[Dukedog]

send an email addy and I will send ya a pretty detailed manual in pdf if ya want.. has several motors including yours....

 

[BoaterBor]

rnottb@aol.com
Thank You

 

[jerryjerry05]

Last week working on a 99 200 EFI
The alarm sounded off, continue's to sound off.
Not overheating.
Turns out the fuel filter on the motor was almost full of water.
I'd heard that that was supposed to be an intermittent signal???

 

[Dukedog]

Turns out the fuel filter on the motor was almost full of water.
I'd heard that that was supposed to be an intermittent signal???

yeah, supposed ta be a beeping, not solid.. signal is supposed to go thru tha oiler module.. any signal coming out of tha module is supposed ta be a beeping signal?.. that's tha sole job of tha module.. do you get tha series of "test" beeps when key is turned on?