Yamaha F400A 2022 - Checking the Direct Injection Pump

Fuel control unit and component
5-30
d. Disconnect the low-pressure fuel
pump coupler “c”.
e. Measure the resistance of the fuel
pump motors.
Out of specification → Replace.
f. Connect the low-pressure fuel pump
coupler and high-pressure fuel pump
couplers.
Checking the direct injection pump
1. Check:
• Direct injection pump
a. Check the operation of the direct injec-
tion pump using the YDIS “Stationary
test” and check the operating sound.
b. Disconnect the direct injection pump
couplers “a” and “b”.
c. Measure the resistance of the fuel
pump solenoid.
Out of specification → Replace the di-
rect injection pump.
High-pressure fuel pump
Input voltage
12 V
Yellow/Red (Y/R)–Blue/Red (L/R)
Y/RL/R Y/RL/R
a
b
A
c
A. Low-pressure fuel pump
B. High-pressure fuel pump
Low-pressure fuel pump
Resistance (reference data)
0.6 Ω
High-pressure fuel pump
Resistance (reference data)
0.3 Ω
BB
a
b