Yamaha YP250R 2005 Service Manual page 286

CARBURETOR
3. Check:
• auto choke unit (with battery)
M MMM M MMM M M MMM
a. Connect the auto choke unit lead to a
12.0 V battery for five minutes.
Positive battery lead → yellow 1
Negative battery lead → green/black 2
b. Connect a 3.3 mm (0.13 in) hose 4 to the
starter air passage 3 and blow into the
hose.
Starter plunger opens
Replace the auto choke unit.
Starter plunger closes
Auto choke unit is OK.
L LLL L LLL L L LLL
7 - 9
CARB
M M MMM M M MMM M
L L LLL L L LLL L
M MMM M MMM
L LLL L LLL