Yamaha SXV70ERG Supplementary Service Manual page 22

Remove the cover.
Check if there is any
freeplay on the Y.P.V.S.
cables.
No freeplay
Start the engine.
Are the warning light and
LCD lit?
Yes
With the engine running at idle
speed, check that there is freeplay
on the Y.P.V.S. cables.
No freeplay
Adjust the idle speed below 900
r / min.
* The valve fully opens below
1,000 r / min.
Check that the warning light and
self-diagnosis warning indicator,
lights up.
Does not light up
The Y.P.V.S. is ok. Adjust the
idle speed to specification.
S If the valve is stuck, inspect it and then either remove any carbon or reassemble the valve, refer to the
"YAMAHA POWER VALVE SYSTEM (Y.P.V.S.)" in CHAPTER 5.
S If the valve is not stuck, but the warning light and self-diagnosis warning indicator remains lit, refer to
the "SELF-DIAGNOSIS" in CHAPTER 8.
YAMAHA POWER VALVE SYSTEM
(Y.P.V.S.) PRE-SEASON CHECKS
Freeplay
* The valve maybe stuck in
the fully-opened position
and the servo motor maybe
fully closed.
Replace the bulb of warning
light or the LCD.
No
Freeplay
* There is freeplay because the
valve is either stuck in the
half-or fully-opened position.
Does the warning light
and self-diagnosis
Light up warning indicator blink
seven times in five
seconds?
No
Refer to "SELF-DIAGNOSIS" in
CHAPTER 8.
–16–
INSP
ADJ
Turn the pulley to remove
the freeplay.
Yes
* If the valve is stuck
in the fully-closed or
half-opened position,
the diagnosis function
may indicate a faulty
servo motor.