F225txrd ECM / wiring questions

[fairdeal]

While I still remember where the diagram is located in the SM, I've been enjoying looking closer.

I'd like to get confirmation that I am understanding: a few questions on the section below



1. The red circle is the "ignition switch?
2. The green circles are "key on" aka "ignition" power ?

3. At "key on" :
power is applied to Terminal 28
with that, the ECM applies "ground" to Term 2
which closes the Main relay, supplying power to Term 30
(and also to "the red/yellow wires")

Yes?

thanks!

[boscoe99]

That is the way that I see it.

[fairdeal]

Thank you, Boscoe.

OK, here's my next question
(and again, this schematic is from F200/225 LIT-18616-02-76 printed 2003)



Pin 24 - Oil pressure warning Lamp - check!

Pin 23 - Overheat warning Lamp - check!

Pin # 27 - "Engine Warning Lamp" ????

[boscoe99]

Check engine function.

[rodbolt17]

which may or may not be used on your model .

[fairdeal]

Check engine function.

which may or may not be used on your model .

Right.

But Yamaha is publishing that in the SM for the F225 - in 2003 - so doesn't that mean that at least the, what, 2003 model ? has that function?


I have a "2005" model, so .......maybe different anyway.

Nonetheless, interesting about the Tach being able to display that icon.

Here's mine:




I recall when I removed and sold my speedometer, I noticed it did a "power on self test" of the display.

Never noticed if the tach does that, too - would I momentarily see everything that the screen might possibly display?

I'm gonna run downstairs and have a look...

[boscoe99]

Some Yam tachometers have the check engine icon and some don't.

Some Yam motors output a check engine ground and some don't.

I suspect a 2005 Yam F225 outputs the check engine function but maybe not.

Yam likes to keep folks guessing about what does what and when. They are niggardly with their data and don't like to tell their folks much about it.

When they do they put some of the information up front in a SM where folks won't look and then leave it out in the part of the manual where one would expect it to be.

[fairdeal]

Thanks, Boscoe.

So I don't know if this is "conclusive" as to the tach capability but here's a quick shot at "power on"



Not seeing the "water in filter" icon, either, brings up more questions.

You & Rodbolt have previously identified the presence of the water detector wiring in the harness of my engine (I posted a photo).

So I suppose I could play with that, see if I can make that icon show up...

But now that I look, I see nothing on that ECM schematic related to the filter water sensor -

so how is that alarm "triggered"?

I very much appreciate you guys indulging my curiosity!

[boscoe99]

Some M/F tachometers have the check engine icon and water in fuel icon and some don't. If you don't see the icons at the initial power up yours does not.

Some motors output the check engine ground and some output the water in fuel ground and some don't.

I recall certain early HPDI's outputting the water in fuel ground. I don't think early F225's do.

I doubt very seriously that the HPDI, F225 and tachometer Yamaha engineers talked to each other back in Japan. They sure as heck did not proof read the manuals the Yamaha tech pubs people produced.

[fairdeal]

Some M/F tachometers have the check engine icon and water in fuel icon and some don't. If you don't see the icons at the initial power up yours does not.

Ok then.

I have wondered, but the language barrier makes it impossible to even know -surely there are Japanese language forums like this ?

I imagine retired electrical and mechanical Yamaha engineers, passing the time on the internet: answering queries and sharing the full and precise details of so many things we just guess at?

oh well.

By the way - in that sample Tach you posted above: what are the light/dark (full/empty ?) icons ?

[boscoe99]

The tachometer shown is set up for the two stroke mode. There are normally three bars displayed which means all is well.

If the right bar disappears and the middle bar starts flashing it means the remote oil tank is low but there is oil in the main oil tank.

If the middle and right bars are missing and the left bar is flashing it means the remote tank is low and the main tank is low. The horn should also be sounding and the motor should be in RPM reduction mode.

If all three bars are flashing it will mean the remote tank has oil but the main tank is low. A restricted oil filter could cause this.

See below. You were asleep the last time I posted it.