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Honda BF50 Alarm

N

nomi

Member
I have a late 90s BF50. The indicator lights have never worked since i got it, but never had any issues for at least a year until this solid alarm started. The alarm itself is inconsitent, sometimes it'll happen within a minute of start up. Sometimes i can run for an hour before it starts.

Its not the trim alarm, i already disconnected that. Whixh should narrow it to either oil pressure or temp. Except i disconnected both those wires at the engine cross connect -- yet the alarm still sounds!?

Today i figured out that i can make the alarm go away if i disconnect the temp and/or oil pressure wires at that little indicator light box mountes in the console. But once again, its still not consistent; sometimes just disconnwcting the yellow wires works, sometimes just the red -- but then sometimes the alarm comes back manh minutes later at which point i can make it go away by disconnecting both.

I also notice that the engine will bog if i try pushing thru the alarm, but if i disconnect the wires at the module it wont bog.

I have a couple questions:

1. Is my issue the indicator light box itself? Or a short further up the line? Or something else?

2. Does that indicator light box have any brains in it that actually interprets the sensors signals & governs the motor if necessary (or does that function take place under the cowling)? If not, then why does disconnecting it eliminate the bogging?

Thanks for the help
 
Find out if your motor has a thermo switch or ect overheat sensor the way you can tell is check the wires at the indicator lamps .BL,GR,R,Y colour wires is with a thermo switch and BL,BL&Y,R,Y is with a ect overheat sensor.
 
tegweni said:
find out if your motor has a thermo switch or ect overheat sensor the way you can tell is check the wires at the indicator lamps .bl,gr,r,y colour wires is with a thermo switch and bl,bl&y,r,y is with a ect overheat sensor.
Click to expand...

bl, gr, r, y
 
Gr is for the colour gray so you have an oil pressure switch with a yellow wire that becomes the earth and a red wire for the thermo switch that becomes the earth if they are working the light should light up when the circuit is closed when it opens the light should go off ,the gray wire goes to the regulator rectifier the voltage for the lights comes from there if this is not working your lights wont work at all.
 
Ok thanks for that info...but are you able to give me any guidance in regards to my original questions?

If that light box is inoperable would that cause the alarm on its own? Main priority is to cure the alarm.
 
The thing i dont understand is, i can see how disconecting a wire into the indicator light box would eliminate the alarm. But it surprises me that it also seems to eliminate the safe mode engine limiter -- i would just assume that operation would be controlled entirely inside the engine? But maybe not?
 
Your buzzer has 2 wires Y/G & BL/Y the y/g goes into your icm that is a + wire and the buzzer & lights


















are controlled by 2 negatives which are the yellow & red wires either one of these will set it off because the BL/Y wire is connected to the BL which is the main negative from ignition switch something tells me you have a negative problem in either the oil switch or thermo switch.
 
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Can someone explain how these temp & pressure circuits work?

I would assume that disconnectjng the sensor wire at the cross connect would eliminate the alarm?

OR...if im wrong about that, then the opposite should be true -- disconnecting a sensor should automatically cause an alarm.
 
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