Yamaha 90 aeto electrical gremlin

[seadogg]

Evening, I have an odd one that I cannot get to the bottom of...

Couple weeks ago my tilt/trim motor cut out on the way up and the engine started cranking without the key in the ignition switch. After some checking and head scratching i got the trim motor to fucktion normally bypassing the relay and the engine to crank bypassing the solenoid.

I just fitted a few relay and solenoid and neither work without bypassing them again. I tried fitting another ignition switch I have but it still does the same.

Everything works but only when bypassed

Any ideas?
Cheers

 

[boscoe]

What is the engine serial number?

Did the motor start cranking itself at the exact same time the trim motor stopped working?

 

[seadogg]

90 aeto
6H1K L 1000051

I turned the isolator off to check over why the trim stopped. When I turned the isolator back on the engine started to crank

 

[boscoe]

What is this isolator that you speak of? What is its purpose?

 

[boscoe]

90 aeto
6H1K L 1000051

I turned the isolator off to check over why the trim stopped. When I turned the isolator back on the engine started to crank

Approximately 2003 model year is that correct?

 

[boscoe]

No solenoid used in a 2003 90AETO model. A starter relay only.

If the starter motor is being engaged without the key being in the key switch, when a battery switch is turned to the ON position (assumption being the isolator is a battery switch), and not engaging when a battery switch is in the OFF position, then I would guess that the contacts within the starter motor relay are welded together.

 

[seadogg]

I have replaced the starter relay/solenoid with a new OEM one. I wouldn't of expected a new one to have the same symptoms as the one I just replaced

The battery isolator is just an on off switch wired in after battery, before start relay.

I think I have a bad ground somewhere, possible relating to the 703 controls. Im going to investigate that today