Yamaha 2001, CDI and warning light / sound

[Ole marius Petterson]

Hi

I recently purchased a little used Yamaha F50AET outboard from 2001. When I twist the key the first notch, I expected oil pressure and temperature lights to light up, and then to turn off when the engine is running.

My lights are completely dead...

I have checked bulps by testing the wires that go out of the motor, by putting it to ground (both the green wires, with the ignition on the first notch, without the engine running), and then the lights are working. I think everything is in order from the plug in the engine compartment to the warning lights in the tachometer.




I have short-circuited the temp sensor without light lit up or beeping in the control box, tryed to putting the oil pressure switch to ground, including taking off the cord completely, but no light / sound then either.

Both wires from these sensors enter the cdi box....




Is there someone who has experienced similar problems? Seems to me as if the cdi box is the problem.. -the warning lights do not light up BEFORE the engine is started, nor if they are bypassed as if the engine was too hot or have too little oil pressure ..




Motor is running fine and no other problems ..




Mrs. Ole Marius Petterson

[rejesterd]

Hello. Yes, those lights should come on then go off at key-on.

The easy test for a bad CDI is measuring its output peak voltage at the ignition coil. You need a PV adapter for your multimeter and the peak voltage specs from the service manual.

[Ole marius Petterson]

Well okay, I think I have to take it to a workshop then. I don't have such an instrument.

Thank you very much for your prompt reply :-)

[99yam40]

not so fast, I do not see how the peak voltages going into and out of the CDI would have anything to to with the oil pressure and over temp lights

Hopefully someone knowledgeable on those motors will give some advice on the proper testing of the lights on that motor

[panasonic]

Hello. Yes, those lights should come on then go off at key-on.

The easy test for a bad CDI is measuring its output peak voltage at the ignition coil. You need a PV adapter for your multimeter and the peak voltage specs from the service manual.

Testing for peak voltage out or into the CDI has nothing to do with the warning lights for the engine. That testing is for ignition problems as Yam40 has already said...

Mrs Peterson ignore that advice.

Hopefully Mr Boscoe will dig up the wiring diagram for your engine and post it for all to see.

[Ole marius Petterson]

Thank you, 99yam40 and panasonic :-)




I already have the wiring diagram and it confirms that both of these sensors go into the cdi unit. So I assume that cdi processes the "information" before sending the signal through another line, to the lights and the audio signal.




But unfortunately no signal / earthing / minus comes out of the two cables on the motor side, which goes directly to the light bulbs ..

[boscoe99]

1. I am not so sure that on all Yamaha four stroke models that the lights illuminate when the key is turned to the ON position.

2. There is no thermosensor used on the F50. There is a thermoswitch however. On some Yams when the thermoswitch closes the lights and alarm are not activated immediately. There is a built in delay on some models.

3. The oil pressure switch closing does not automatically sound the alarm or turn on the light on some models. Some models have a built in delay.

4. Jumper the pink wire thermoswitch connector to a good known ground. Start the motor and let it idle for a few minutes. See if the alarm sounds, the light illuminates and if the motor is being operated at a fast idle it might go into RPM reduction mode.

5. I have no idea what testing for peak voltage is all about.

Per Pans request:

[Ole marius Petterson]

Wow! Thank you!! Now I am much more reassured. I have to test this theory on the sea in a few days :-) The form I have found doesn't look exactly the same, but i suppose it is still quite possible that there are delays before sound and light signals start :-)

[rejesterd]

The overheat warning will be delayed 75 seconds after startup if the revs stay under 2000. If you run it above 2000 rpm, it only takes 25 seconds. It should say that in the manual (chapter 1).

The low oil pressure warning will be delayed only 1 second.

Pretty sure the pink is for the oil pressure switch though.

[Ole marius Petterson]

I will test this for sure Thank you rejesterd

[99yam40]

does anyone have the proper wiring diagram for this motor that shows the lights and wiring to them?

[boscoe99]

does anyone have the proper wiring diagram for this motor that shows the lights and wiring to them?

The WD I posted is from a 2003 F50. Thus there may be some differences between that model and the OP's model. And it does appear that Yamaha has once again been inconsistent with respect to wire colours. Thermoswitches are usually pink and black but in that model, for certain years, it appeared they used a different wire colour. They like to keep their mechanics guessing. God help the operator.

[panasonic]

Wow! Thank you!! Now I am much more reassured. I have to test this theory on the sea in a few days :-) The form I have found doesn't look exactly the same, but i suppose it is still quite possible that there are delays before sound and light signals start :-)

Mrs Peterson could you please post all the information on the data plate...serial number.
I think I may have the service manual for your engine.
You say you have the wiring diagram, do you have the proper service manual for your engine??

[panasonic]

The overheat warning will be delayed 75 seconds after startup if the revs stay under 2000. If you run it above 2000 rpm, it only takes 25 seconds. It should say that in the manual (chapter 1).

The low oil pressure warning will be delayed only 1 second.

Pretty sure the pink is for the oil pressure switch though.

Is this information in the manual for the OP,s engine? Could please share where you got this from.

Thanks

[99yam40]

The WD I posted is from a 2003 F50. Thus there may be some differences between that model and the OP's model. And it does appear that Yamaha has once again been inconsistent with respect to wire colours. Thermoswitches are usually pink and black but in that model, for certain years, it appeared they used a different wire colour. They like to keep their mechanics guessing. God help the operator.

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)?