Warning horn on 1990 Johnson GT150

[Further North]

Continuous tone...supposed to be either over-heating (it's not, running nice and cool) or something wrong with the fuel supply.

It's not all the time, and it will come on as soon as the ignition is turned on, and stay on...except when it doesn't....

Cleaned out the filter, checked to lines for leaks and kinks...boat runs fine, all the way to max rpms and top speed...

Tonight it comes on then fades out right away (a second or less) like it's supposed to.

Yesterday it came on and stayed on. I've touched nothing in between...

I'm at a loss.

 

[boobie]

Re: Warning horn on 1990 Johnson GT150

Sounds like you have may have a grounded tan wire at times from the control box back to the mtr or a bad horn.

 

[emdsapmgr]

Re: Warning horn on 1990 Johnson GT150

A defective fuel vacuum switch will also set off a horn on that model.

 

[Further North]

Re: Warning horn on 1990 Johnson GT150

OK, finally had time to work on it a little...

Checked where the temp sensors are in the cylinder heads, tracked the wires back to where they join the main harness...no visible problems.

Had the bright idea to pull the tan wire off the horn itself...that did it - warning went back to normal when ignition is turned on.

 

[winfieldh]

Re: Warning horn on 1990 Johnson GT150

I'm working on a similar issue and want to assure you I know nothing compared to the other folks here, but.....I think removing the tan wire from the horn itself actually renders your engine sensors worthless. So if the motor were to overheat/run out of oil/what ever else the sensors are designed to protect you against, they won't. I may be totally off base so wait for further response.

Cheers

 

[Joe Reeves]

Re: Warning horn on 1990 Johnson GT150

Winfieldh is correct..... re-connect that TAN wire or chance an assortment of problems. See my comments to subject "1988 Johnson 150 ignition alarm question" on this same site.

 

[Further North]

Re: Warning horn on 1990 Johnson GT150

I plugged it back in - I'd never run it like that. It was just a diagnostic step.

I will follow up on that posting, thanks.

 

[Further North]

Re: Warning horn on 1990 Johnson GT150

Went out to work on it today and the !@#$%&*^ horn is working perfectly.

 

[Further North]

Re: Warning horn on 1990 Johnson GT150

OK...this is getting silly...went out there again, on a hunch...turned on ignition, horn went on and stayed on.

Shut off ignition.

Went to motor, pulled the wire for the port side temperature sensor. Turned on ignition, got the "normal" chip, then nothing.

"AHA!", sez I, "that must be it!"

Turned off ignition, plugged the sensor back in, expecting the continuous tone...and I got the "normal" chirp again.

&^%#!@#$%

 

[Further North]

Re: Warning horn on 1990 Johnson GT150

Found the vacuum switch...that's fine...

...went back to the sending unit on top of the oil tank...wiggled the wires a little...got a chirp...turned them a little more...the horn came on.

Must be some kind of short in there somewhere. Turned the wires so that they are running straight off the side of the tank (they were coming out of the sending unit, than kind of bent over themselves at a 90? angle), gathered up all the extra wire (must be 6 ft. of it) and zip tied it so it's not pulling the wire off to the side.

There's still obviously a short in there someplace, but now that I know what it is I'm more relaxed...can the sending unit be disassembled and the wires re-done, or am I looking at a whole new unit?

 

[boobie]

Re: Warning horn on 1990 Johnson GT150

1995 and prior oil tanks had a bad habit of giving off false signals to set off the horn. In 1996 the tanks just had an on-off switch in them rather than electronics.

 

[Further North]

Re: Warning horn on 1990 Johnson GT150

Found the vacuum switch...that's fine...

...went back to the oil pick up assembly on top of the oil tank...wiggled the wires a little...got a chirp...turned them a little more...the horn came on.

Must be some kind of short in there somewhere. Turned the wires so that they are running straight off the side of the tank (they were coming out of the sending unit, than kind of bent over themselves at a 90? angle), gathered up all the extra wire (must be 6 ft. of it) and zip tied it so it's not pulling the wire off to the side.

There's still obviously a short in there someplace, but now that I know what it is I'm more relaxed...can the oil pick up assembly be disassembled and the wires re-done, or am I looking at a whole new unit?

 

[boobie]

Re: Warning horn on 1990 Johnson GT150

I'd replace it with a '96 and up sender. Check the Sticky file on top of this forum for salvage yards. If you buy new they are pricey. If you get one make sure it has a black tracer on the tan wire. No electronics.