Checking The Fuel Injectors - Yamaha F115A Service Manual

– +
ELEC
1
8320
1
FUEL CONTROL SYSTEM
8330
8340

CHECKING THE FUEL INJECTORS

1. Check:
• Fuel injector operating sound
No sound (no fuel is being sprayed) →
Check the high-pressure fuel pump.
Checking steps
(1) Start the engine.
(2) Fully close the throttle valves.
(3) Attach the screwdriver 1 onto the fuel
injector body and check if all of the fuel
injectors have a solenoid valve operat-
ing sound.
2. Check:
• High-pressure fuel pump operating
sound
Correct → Replace the fuel injector (no
sound).
No sound → Check the main relay.
NOTE:
• The high-pressure fuel pump should
sound when the engine start switch is
turned on.
• Disconnect the Brown (Br) starter relay
lead 1 to prevent the engine from start-
ing.
3. Check:
• Main relay continuity
Out of specification → Replace the
main relay.
Engine
R
R/Y
start
R/Y
switch
G
Y
B
Correct → Replace the high-pressure
fuel pump.
8-21
Lead color
Red (R)
OFF
ON
E
8
Red/yellow
(R/Y)