F225 starting issues

[pstephens46]

hahahaah
to stupidly simple.
should have been caught by a 2nd week student at MMI.
and the description is all wrong. it is a switch, that switch tells the motor NOTHING.
cannot be monitored with YDS.
if it is open current simply wont flow.
your chain got yanked.

How is a code 28 generated? Isn’t that a result of trying to start motor in gear?

[fairdeal]

How is a code 28 generated? Isn’t that a result of trying to start motor in gear?

great question! looking forward to hearing from Boscoe and Rodbolt





its my (limited) understanding that the only purpose of the "neutral switch" -
the one in the bottom cowling, on the shift cable slide -
is to enable the ECM to limit RPMs when the engine is in neutral

but what is an "incorrect signal"?

how can/does the ECM decide what is "incorrect"?

now, Code 45 - "incorrect Shift Cut Signal" - seems plausible to me
since there is a parallel resistor within the switch,
the ECM is able to detect "no switch present"
- presumably what is considered "incorrect"

[pstephens46]

Hmmm. I thought, perhaps incorrectly, the neutral switch was used in the start sequence. How does the ECM “know” the motor (my F150) is in gear and then prevent “turning over”? Hell if I know. Maybe I’ll learn something today. Damn sure will not learn much over at THT. Too many brand saboteurs running around over there....

[fairdeal]

"turning over" - cranking - is crystal clear,
breathtakingly simple,
and has nothing to do with the ECM

its a "neutral switch" inside the "remote control" - throttle/shift lever -
that allows, or not, the starter motor to run.

[rodbolt17]

yall gots to stop and think.
use the ole tool twixt the ears.

that switch on the engine simply tells the ECU is it in a gear position or not. has nothing to do with starting.
the switch or LPS in the control box at the helm determines whether the engine will crank or not.

[fairdeal]

that switch on the engine simply tells the ECU is it in a gear position or not.

understood. And understand that it limits rpms when "not in gear".


but how/why does the ECM throw a #28 "Incorrect neutral switch signal" ?

[99yam40]

I am fairly sure that if the ECU sees or thinks the motor is not in neutral when it gets started it would throw the code.
bad switch,adjustment, or wiring

[fairdeal]

I am fairly sure that if the ECU sees or thinks the motor is not in neutral when it gets started it would throw the code.

well, certainly the ECM knows when the flywheel is spinning - or not
which is why it sounds the alarm horn when the starter spins with the killswitch "on"

but with the killswitch "off":
it doesn't mind running while in gear - that's normal
nor does it mind running in neutral -
nor not running in neutral !

I suppose it could be programmed to "detect" the "transition from stopped to spinning"
while in gear

but I do not recall having read of that, either in Yamaha literature, or here

[99yam40]

I would think that it sets the code because the motor started without it in neutral.
wants someone to fix that as it is not suppose to do that for safety reasons

[rodbolt17]

there were some yamahas that used 3 switchs,one cut ,one fwd and one rev.
my bet is it was a translation error.
99% of them say shift position switch.
some engines if it is not in N when it starts it may limit RPM to about 4300.

[Jfitz1949]

This is the culprit. Corroded plug, middle wire.

[Jfitz1949]

This is the culprit. Corroded middle pin and socket.

[oldmako69]

Where does that plug reside?