Komatsu PC200-8M0, Shop Manual

Page: 846 / 1254

400 Troubleshooting of electrical system (E-mode)
E-7 Fuel level gauge does not indicate properly
40-400
24
PC200, 200LC, 220, 220LC-8M0
SEN06138-00
E-7 Fuel level gauge does not indicate properly
Circuit diagram related to fuel level sensor
Failure
1) While fuel is added, fuel level gauge indicator does not rise above red range (E).
2) While fuel level is low, fuel level gauge indicator does not lower below green range top (F).
Related infor-
mation
q Signal voltage of fuel level sensor can be checked with monitoring function.
(Code: 04200 Fuel sensor voltage)
Cause Procedure, measuring location, criteria and remarks
1
Defective fuel level sensor
(internal open or short cir-
cuit)
1. Turn starting switch to OFF position.
2. Disconnect connector P21 and connect T-adapters to male side.
Between P21 (male) (1)
and ground
Fuel level: FULL Resistance 7 to 11
z
Fuel level: EMPTY Resistance 85 to 95
z
2
Open circuit or ground fault
in wiring harness
1. Turn starting switch to OFF position.
2. Disconnect connector CM01 and connect T-adapter to female side.
Between CM01(female)
(15) and ground
Fuel level: FULL Resistance 7 to 11
z
Fuel level: EMPTY Resistance 85 to 95
z
3
Open circuit in wiring har-
ness
(wire breakage or defective
contact of connector)
a
If no failure is found by check on cause 2, this check is not required.
1. Turn starting switch to OFF position.
2. Disconnect connectors CM01 and P21, and connect T-adapters to each female
side.
Between CM01(female) (15) and P21(female) (1) Resistance Max. 1
z
4
Ground fault in wiring har-
ness
(contact with ground circuit)
1. Turn starting switch to OFF position.
2. Disconnect connectors CM01 and P21, and connect T-adapters to either female
side.
Between CM01(female) (15) and ground, or between
P21(female) (1) and ground
Resistance Min. 1 M
z
5
Hot short circuit in wiring
harness
(Contact with 24 V circuit)
1. Turn starting switch to OFF position.
2. Disconnect connector P21.
3. Insert T-adapters into connector CM01 or connect T-adapters to female side of
connector P21.
4. Turn starting switch to ON position.
Between CM01(15) and ground, or between P21
(female) (1) and ground
Voltage
Approx. 3.3
V
6 Defective machine monitor
If no failure is found by above checks, machine monitor is defective. (Since this is
an internal defect, troubleshooting cannot be performed.)