F225TXRD warning lamp self-test

[fairdeal]

The sad thread about the analog tach whose warning lamps fail to self-test at key on got me curious.

I'm used to the Yamaha multifunction tach, which itself does a self-test of the entire display at key on.

I wondered, what does the F225 ECM do.

So I disconnected the trim /oil lead at the engine, and rigged a couple of LEDs -
powered by the hot lug, and then to the overheat and oil pressure pins -


[

Turns out, the ECM grounds (lights) the warning lamps for ~3 seconds at key on.





Video of turning 'key on' and then off:


https://vimeo.com/335386435

[boscoe99]

The same ground either causes lights to illuminate in a 6Y7 analogue tachometer or liquid crystals on the 6Y5 multi-function tachometer to illuminate.

I had the analogue Yamaha tachometer with lights (6Y7) when I had my F200. Both lamps would light up for several seconds upon engine start up. Maybe just key on.

I know that not all Yams act the same. I can't say what any other Yamaha models would do with respect to lights. I have had my arse handed to me on a platter on several occasions when I thought that one model was similar to a different model. Hell, I still git bit from time to time.

[boscoe99]

What is the funky noise at the end of the video? Is that the balancer failing?

[99yam40]

I thought he said just turning the key on and then off, nothing about starting the motor.

and what was the clicking noise at the beginning

[fairdeal]

What is the funky noise at the end of the video? Is that the balancer failing?

haha yes it would be, on THT!

That's my Lenco trim tabs - there's a feed from ignition - they automatically 'reset' at key off.


which brings up the noise at the beginning of the video - which is the IAC being reset.


We always tell folks to listen for it when shutting down after running - that's a given.


But clearly there is some interesting logic in the ECM;

I had key on/off several times getting set up for the video - but never started the engine.

First time at key on, all I heard was the HP pump - as expected.

But subsequently every time at key on, the ECM reset the IAC.

(couldn't hear if the HP pump ran, because IAC was louder)

And the IAC never cycled at key off - presumably because the ECM "knew it hadn't run."

[pstephens46]

But clearly there is some interesting logic in the ECM;

I had key on/off several times getting set up for the video - but never started the engine.

First time at key on, all I heard was the HP pump - as expected.

But subsequently every time at key on, the ECM reset the IAC.

(couldn't hear if the HP pump ran, because IAC was louder)

And the IAC never cycled at key off - presumably because the ECM "knew it hadn't run."


[/QUOTE]

That’s interesting. I remember a thread here where an OP was reporting the IAC clicking at key on. Which worried some of us. Perhaps that was correct operation after all. I’ll dink around with mine a bit and see if I get similar results