90 HP Yamaha ignition boxes going bad

[briarblu72]

I have a 90 HP Yamaha manufactured 3/99. The boat has always been stored inside and was running good but was not used this winter. When I got it out it would not crank. No fire to #2 and only momentary fire to #1&3. A local shop replaced the control box which they said was only sold by Yamaha at almost $600. The boat ran great for one full day but the next morning the same fireing symtoms as before. Any help would be appreciated.

 

[rodbolt]

Re: 90 HP Yamaha ignition boxes going bad

did they replace the control box or the CDI assy?
did they test pulser coil output voltage while it was failing? did they test all grounds.
that system uses 1 pulser coil to control the trigger for cylinders 1 and 3, cyl two is controled by the CPS,crank position sensor.
stator charge coil provides the ign operating voltage for all 3.
lose a pulser and you lose 1 an3 and sometimes 2 as well. lose a charge coil and you lose all 3,lose a CPS and you lose cyl 2. CPS is crank position sensor.

all inputs to the CDI assy are testable.
all outputs are testable.
good inputs and bad outputs are bad CDI, bad inputs are automatically bad outputs.