Yamaha VMX12 2001 Service Manual page 442

5. Fuel reserve switch
• Check the fuel reserve switch for continuity.
Refer to "CHECKING THE SWITCHES".
• Is the fuel reserve switch OK?
YES
6. Fuel level indicator light bulb and socket
• Check the fuel level indicator light bulb and
socket for continuity.
Refer to "CHECKING THE BULBS AND
BULB SOCKETS".
• Are the fuel level indicator light bulb and
socket OK?
YES
7. Fuel sender
• Drain the fuel from the fuel tank and remove
the fuel sender from the fuel tank.
• Disconnect the fuel sender coupler from the
wire harness.
• Connect the pocket tester (Ω × 1) to the fuel
sender coupler as shown.
Positive tester probe → green 1
Negative tester probe → black 2
• Measure the fuel sender resistances.
NO
Replace the fuel
reserve switch.
NO
Replace the fuel level
indicator light bulb,
socket or both.
FUEL PUMP SYSTEM
Fuel sender resistance
(Ω × 100)
700 ~ 1,100 Ω at 25 °C
• Is the fuel sender OK?
8. Fuel pump relay
• Connect the pocket tester (DC 20 V) to the
fuel pump relay as shown.
Positive tester probe → blue/black 1
Negative tester probe → black 2
• Start the engine.
• Measure the fuel pump relay output volt-
age.
Fuel pump relay output voltage
12 V
• Is the fuel pump control unit OK?
8 - 50
ELEC
YES
Replace
sender.
YES
Replace
pump relay.
– +
NO
the fuel
NO
the fuel