2003 Z150TRLB ECM Main Relay Issue

[rejesterd]

I would certainly like to know more about this.

Can you elaborate for us, exactly how this "output of the ECM" goes "to the ignition coils" ?

Yeah, I'll rephrase it.

The ECM is wired into the primary ignition circuit. You can usually see that on your wiring diagram. The black/red and black/white wires. The ECM receives a signal from the pulser coil, then it interrupts the primary circuit. This in turn, collapses magnetic field and produces the spark in the secondary circuit. In TCI, the battery is directly responsible for creating that magnetic field. But the ECM determines when that magnetic field collapses. If the ECM or the pulser coil is not doing its job, the output peak voltage in the primary circuit will be lower than the manual spec.

[boscoe99]

Methinketh too many cooks spoileth the broth.

[fairdeal]

Methinketh too many cooks spoileth the broth.

well, we are all posting here for our own amusement,
some personal sense of self-satisfaction,
in displaying our 'knowledge'.

Some - like yourself and Rodbolt - actually provide useful information.

But no doubt the rest of us think we do...

[pstephens46]

well, we are all posting here for our own amusement,
some personal sense of self-satisfaction,
in displaying our 'knowledge'.

Some - like yourself and Rodbolt - actually provide useful information.

But no doubt the rest of us think we do...

I really wish Rodbolt would focus in on these HPDI threads. They are in a class by themselves and we all can learn.

[boscoe99]

I am done with this thread. Hoping we can start over.

[99yam40]

I didn't say the ECM generates voltage. Maybe I incorrectly worded it in my first draft, but the quote you noted is what I ended up posting. I said you have to measure the peak voltage from the output of the ECM going to the ignition coils.

so are you are agreeing this peak voltage from the ECU to the ignition coils you are talking about is just 12 volt battery voltage or is it something different??

[rejesterd]

so are you are agreeing this peak voltage from the ECU to the ignition coils you are talking about is just 12 volt battery voltage or is it something different??

No. The battery powers the primary ignition circuit. The transformer in the ignition coil is what produces the 200+V output. And this is managed by the ECM.

[boscoe99]

What ECM output to the ignition coils?

The ignition coils are powered by battery DC voltage. Never heard of checking battery voltage with a peak voltage meter.

This thread gets curiouser and curiouser.

[rejesterd]

What ECM output to the ignition coils?

The ignition coils are powered by battery DC voltage. Never heard of checking battery voltage with a peak voltage meter.

This thread gets curiouser and curiouser.

The ECM is wired into the primary ignition circuit. Maybe "output" was the wrong word, but I already re-phrased it above for fairdeal.

[99yam40]

The ECM is wired into the primary ignition circuit. Maybe "output" was the wrong word, but I already re-phrased it above for fairdeal.

the whole point of this questioning is that you feel that more than 12 v DC goes into the primary of the coils it seems.
It does not.
the ECU stops the flow of 12 volts to the coils to collapse the field and send spark voltage from the secondary to the plugs

[rejesterd]

the whole point of this questioning is that you feel that more than 12 v DC goes into the primary of the coils it seems.
It does not.
the ECU stops the flow of 12 volts to the coils to collapse the field and send spark voltage from the secondary to the plugs

12V powers the primary ignition circuit. When the primary circuit is interrupted by the ECM, that's when the 200+V goes through the secondary circuit and across the spark plug gap.

[fairdeal]

"rejesterd" means well I'm sure,
but in his enthusiasm, got in 'over his head'
and is trying to tap dance his way out, dignity intact.

Been there.

My criticism is for Yamaha and their terminology -
why would they call it "ECM output peak voltage"
when it is voltage induced in, and by, the primary coil

Yes, the ECM 'sets the stage for it',
and grounds it -
but - IMO - calling it "ECM output" sends us -
to use "rejesterd's phrase -
down a rabbit hole.

[rejesterd]

why would they call it "ECM output peak voltage"
when it is voltage induced in, and by, the primary coil

Because the ECM is wired into the ignition circuit.

If you were senior editor, how would you edit the manual?

[99yam40]

12V powers the primary ignition circuit. When the primary circuit is interrupted by the ECM, that's when the 200+V goes through the secondary circuit and across the spark plug gap.

so you are saying that 200V or close to that is what jumps the spark plug gap to fire the cylinders?
or that the 200v is going into and out of the ECU?

On cdi ignition systems around that is what goes into the primary of the ignition coils and the secondary is in the thousands of volts at the plugs.
on these systems it is only 12 V going in, but you can bet it will be higher than hundreds hitting the plugs

[boscoe99]

We all (me especially) need to be careful what we write now. Since there is no way for me to go back and edit or delete crap information.