Yamaha engine dies

[aldon2432]

I have a 2008 Yamaha 150HP, 4 stroke engine that often dies for no apparent reason. Starter will not engage and trim tilt will not work, totally dead, but horn will work and dash instruments work. Dealer has not been able to find problem. Wait 10 to 45 minutes and it will start and run just fine until it dies again. Engine does not miss, backfire or anything, it just dies. I have noticed after some minutes, a rapid clicking noise from the engine then it will start and run fine maybe a few minutes or rest of the day. Battery is new and tested OK.
Someone said could be problem with the Electronic Control Module. Any advice welcome.

[boscoe99]

I will say that it could be the ECM. But I will also say that most likely it is not. In fact, I think the ECM will be the least likely source of the problem.

How are your trouble shooting skills? Do you own a multi-meter and know how to use it? Do you have a copy of the service manual for your model and do you know how to read a wiring diagram?

Now just for the hell of it I would pull all fuse and inspect them for cleanliness, tightness and any signs of distress. Maybe pull the main relay and do the same for it.

[99yam40]

Sounds like bad connection causing voltage loss to fuel pump T&T, and start circuit.
If it is doing it often then you should be able to measure and find out where there is good voltage and where it is not when problem shows up to pinpoint where the problem is located

[Nautical]

Might look into the key switch and /or the kill switch for good connections and functionality. Go over all your electrical connections and grounds.

[rodbolt17]

key switch wont kill the trim.
a bad connection at the 10 pin ,a bad harness extension under the deck or a bad battery cable will.
next time it happens try the pan trim switch, if that works and the helm switch does not then focus on the harness.
if both switchs wont work, focus on the battery cable/switch.

see how easy this trouble shooting is???