Yamaha P150TLRX No spark on 2 & 5

[kkellogg13]

I have a Yamaha P150TLRX and it isn't firing on Cyl's 2 & 5.

After replacing the CDI Box, and the Crank Pos Sensor (which i thought 2 & 5 were off of) I Still have no spark on 2 & 5. I even went as far as buying the winky blinky and that won't even work. It doesn't show any light codes at all.

The only thing I've found is that the remote switch for the oil isn't working (and i know the blue lead from the winky blinky connects to that.)

I tested for ground and power for the remote switch and i have both of those.

Any help would be greatly appreciated! Thanks in advance!

-Kyle

[boats.net]

Need to test Pulsor coils.

[rodbolt17]

need to test the crank position sensor output voltage.
if its good carefully test the wiring from the connector to the ecu.
lose a pulser coil on that engine and you lose 2&5 and whatever two coils the failed pulser coil controls.
you also need to check for 12v at the yellow ECU bypass wire.
lose that and you lose 2 and 5.
you also lose timing advance at cold start.

[kkellogg13]

Does the yellow bypass wire get the 12v from the CDI side or from the harness side?

[rodbolt17]

I dont think the p150 can use the winky blinky.
if your manual transfer switch doesnt work check the switch and the switch grounds.
all the manual switch does is manually grounds the blue wire for the oil transfer pump bypassing the ECU.
my guess is the bypass voltage comes from the CDI via key on yellow.
dont have access the internal CDI diagrams but the bypass wire comes out of then goes back into the CDI.

[kkellogg13]

Thank you for the help! The problem is finally solved!

The yellow bypass wire wasn't getting 12v. Instead of tracing where the loss of power was in the harness i ended up running a new yellow from the key switch to the bypass on the CDI, all cylinders are running, the tach, and the oil switch work aswell too!

I'm amazed that the service repair manual said nothing about checking this particular wire. Even the tech guys at Yamaha and some people at a nearby Yamaha dealer didn't even suggest that this might be the problem!

Once again thanks for the help!

-Kyle

[99yam40]

Apparently your CDI has a problem if you lost the 12 volt+ from it

Not sure what adding another source can do but might need to check on that

[rodbolt17]

see how easy this is?
its simple if you understand the system and what happens if something isnt there.