Yamaha F75F - Checking the High-Pressure Fuel Pump Relay

Fuel control unit and component
5-24
c. Turn the engine start switch to OFF.
d. Connect the high-pressure fuel pump
coupler.
3. Measure:
• High-pressure fuel pump resista
nce
Out of specification  Replace.
a. Disconnect the high-pressure fuel
pump coup
ler.
b. Measure the high-pressure fuel pump
motor resist
ance.
c. Connect the high-pressure fuel pump
coupler.
Checking the high-pressure fuel
pump relay
The high-pressure fuel pump relay cannot be
removed for testing or replaced as a single unit
because it is a component part of the fuse box.
See “Fuse box” (2-11).
1. Check:
• Trouble code on the
YDIS
See “Troubleshooting procedure” (4-4).
2. Measure:
• Main fuse input volta
ge
See step (2) in “Checking the main relay”
(5-18).
Checking the vapor shut-off valve
1. Measure:
• Vapor shut-off valve input voltage
Out of specification  Check the
wire har-
ness for continuity.
a. Disconnect the vapor shut-off valve
coupler “a”.
b. Turn the engine start switch to ON,
and then
measure the input voltage
between the vapor shut-off valve cou-
pler terminal and ground.
c. Turn the engine start switch to OFF.
d. Connect the vapor shut-off valve cou-
pler.
2. Check:
• Vapor shut-off valve operation
Not operating  Replace.
a. Remove the vapor shut-off valve, and
then
connect the special service tool
“1” to the vapor shut-off valve.
b. Apply the specified negative pressure
to the vapor shut-off
valve.
A. F75FEHT, F100GEHT
B. F75FET, F100GET
Resistance (reference data)
0.7 
a
R/Y
L
B
Input voltage
12 V
Red/Yellow (R/Y)–Ground
R/Y
a