Komatsu PC58UU-3 - Fuel Level Gauge Indicates Abnormally; A) All Segments of Fuel Level Gauge Go off; B) Fuel Level Gauge Keeps Indicating Full While Fuel Is Consumed

20-610 PC58UU-3
TROUBLESHOOTING
M-10 Fuel level gauge indicates abnormally
a) All segments of fuel level gauge go off
b) Fuel level gauge keeps indicating full while fuel is consumed
Cause Remedy
• Connect short connector to M1
• Turn starting switch to ON.
• Wait for about 1 minute.
1
Does fuel level gauge indicate full (do
all segments light up)?
NO
YES
Defective fuel level sensor
(internal disconnection)
Replace
2
• Short F27 (7) to (3), (4).
• Turn starting switch ON.
• Wait for about 1 minute.
Does fuel level gauge indicate full?
NO
Defective monitor panel Replace
YES
Disconnection or defective
contact in wiring harness
between F27 (female) (7) –
M1 (female) (1) or between
M1 (female) (2) – chassis
ground
Repair or
replace
Cause Remedy
1
Disconnection or defective
contact in wiring harness
between F27 (female) (3), (4)
– chassis ground
• Start engine.
• Max. 0.1 V.
Is voltage between F27 (3), (4) and
chassis normal?
NO
Repair or
replace wiring
harness
• Remove sensor.
• Move float with hand and mea-
sure resistance between M1
(male) (1) and (2).
• F position: Max. 10 z
• E position: Min. 85 z
• Disconnect M1
YES
2
Is resistance of fuel level sensor nor-
mal?
NO
Defective fuel level sensor Replace
YES
3
Short circuit with chassis
ground in wiring harness
between F27 (female) (7) –
M1 (female) (1)
Defective monitor panel
• Disconnect M1
• Turn the starting switch ON.
• Wait for 1 minute
Do all segments of fuel level gauge go
off?
NO
Repair or
replace wiring
harness
YES
Replace
M-10
(6)