Yamaha 2001, CDI and warning light / sound

[boscoe99]

[boscoe99]

why would some of the wires be labeled with colors but not others?

seems to me pink heads to one of the lights on the bottom of the tach even tho they are not labled all of the way there.
the other wire shows to be G/W to G/R to R/blue to G/R again before it hits the tach light on the bottom.
how can the wire color in a cable change colors( from G/R to R/ Blue)?

I suspect that the system was designed so that it was all plug and play. Wire colours would not matter in Yamaha's view. Labeling them in English does the rest of the world no good.

[99yam40]

both short to ground but not sure what color oil is

[rejesterd]

On the OP's main wiring diagram (and on the one I have for the 2001 F50), the oil pressure switch is wired into the CDI unit via a solid pink wire. The thermoswitch is also wired to the CDI via a gray w/ black stripe wire. The feedback from the 2 switches comes out through the CDI wiring harness (via the Y/B and Y/R wires) to a separate 4-pin harness, where they are joined by the green and green with red stripe wires (G, G/R) for the tachometer circuit. The indicator lights are obviously powered by the battery at key-on (via the yellow wire from the remote control box), but ground is through the CDI. That's not to say a peak voltage test will show that the CDI is failing in this way (or at all).. the OP was concerned about a bad CDI, so I mentioned the test for it. But it could just be one of those wiring harnesses or the connection at either end (CDI or tach).

This is made clearer in the smaller diagram for the ignition system earlier in chapter 8.

https://imgur.com/KwWIbCE

The only error I can see is the wire coming from the oil pressure switch going to the CDI. On the main diagram, it's solid pink but on the ignition diagram, it's pink with white stripe. So one of those is wrong, but that's the only hiccup I can see.

[Ole marius Petterson]

I have now been to my local Yamaha workshop. They have long experience with these engines. They have never heard of this problem, that the cdi box or whatever is the problem does not give out signal to light the bulbs for oil pressure and temperature before starting.

Nor have they ever experienced that Yamaha oil pumps stops working.

I was therefore advised not to spend money on a new cdi box, but rather just use the engine as oil pressure probably will not be a problem, and keep up with monitoring the control jet for cooling water, and follow the oil dipstick level.




Hopefully the audio signal will work and notify me IF something should occur.

[rejesterd]

Too bad you couldn't get an answer. Did they run any tests when you took it in, or is this just their reaction to the bad behavior you described?

[rejesterd]

removed: clarification provided in a subsequent comment below.

[Ole marius Petterson]

For economic reasons, I didn't bring the engine to the workshop. I wanted to talk to them first, to hear if it was necessary to hand it in for repair. They thought it was not necessary.




There is at first notch ignition, no voltage over either oil or temperature switch. Totally dead.




I suggested to the workshop not to cut, but connect a wire to the oil pressure cord and the gray wire with the black stripe (the black is earth / minus) on the temp. switch, and connect directly to the lamps. It may, in theory, work, except for the oil pressure switch. There I must have a relay I think, so that I get the opposite "signal" because the oil pressure switch is basically grounded and will lose the connection if the oil pressure goes down.




But again, the workshop thought it was unnecessary to do, and instead just monitor that the engine has enough oil and that the water control beam is fine.

I don't know what else I can do. Right now I have no finances for repairs or new parts ..

[rejesterd]

Oh sorry.. 0V at key-on is correct for these (as they are sensor switches, not just sensors). I would do the test where you short the thermoswitch and run the engine for at least 75 seconds and see if the buzzer & light go on.

[rejesterd]

Also, I would expect the buzzer to sound if you pull the safety lanyard and try to start it. Another quick test for the buzzer at least.

[rejesterd]

Here's another tidbit regarding the remote control box:

https://imgur.com/cCfFl2q

That's from a 703 remote control box manual.

Maybe you just have the model without the buzzer (I didn't know they made these). In the remote control box, that should be the pink wire. If that doesn't go to something round that looks like a buzzer (and is just capped off at some point), then you're probably all set (aside from not being able to know if your engine is overheating).

[fairdeal]

Hopefully the audio signal will work and notify me IF something should occur.

It likely will.
And whether or not you see warning lamps at key on has nothing do with it.

You should understand that the 'warning lights', the audio signal, and the rpm reduction function
are all independent of each other.

The alarm control is of course built into the CDI unit,
the warning horn is built into the keyswitch.

A gauge - with or without warning lamps - is optional.
Not needed.

The engine doesn't need the warning lamps to protect itself.
You don't need to cruise along with one eye on the gauge,
ready to notice if the temperature or oil light comes on.

The only purpose of the warning lights is:
after you have heard the audible alarm -
and perhaps the rpms fall -
you can know whether the alarm is for overheat or oil pressure.

Make sure the horn is capable of sound, and you are good.

[Ole marius Petterson]

I think I have the control with the buzzer in. A white thing inside the box, between the key switch and what we in Norway call dead man's switch. I pulled it out, the starter runs, but the engine does not ignite, and still no sound :-(
I have to troubleshoot even more, because I really want to get the audio signal at least! Thank you for all the tips and information :-D

[Ole marius Petterson]

And yes, i really hope the engine doesn't need the warning lamps or sound TOO, to have ability to protect itself with reducing RPM. Meaning that i hope that part of the cdi works even the lights and sound is faulty.. 😱

[rejesterd]

Do you see a round plastic part that has a pink and a yellow wire coming out of it? If not, then you don't have a buzzer. Maybe you can take some pictures of the control box with the panel removed. I actually don't know where it sits (whether it's in the remote control box itself or if it's behind a gauge on the console), but I would like to see it. I would open up my dad's 2001 F50 to confirm, but our camp hasn't opened yet.

I would say the CDI is fine though (especially if it runs well at cruising speed). You can always buy the buzzer and install it at some point if it's not there. But if it's not installed, then I think what you're seeing is completely normal.