Suzuki Grand Vitara Service Manual page 152

1A-145 Engine General Information and Diagnosis:
Step
7 Short circuit check for fuel level sensor output signal
circuit
1) Turn ON ignition switch and measure voltage between
"E23-24" terminal of ECM connector and vehicle body
ground.
Is voltage 0 V?
8 Open circuit check for fuel level sensor output signal
circuit
1) Disconnect fuel pump connector referring to "Fuel Tank
Removal and Installation: in Section 1G".
2) Check for proper connection to "YEL/RED" and "YEL/
GRN" wire terminals of fuel pump connector.
3) Connect connectors to ECM.
4) Turn ON ignition switch, measure voltage between "YEL/
RED" wire terminal of disconnected fuel pump connector
and vehicle body ground.
Is voltage 10 – 14 V?
9 Open circuit check for fuel level sensor output signal
circuit
1) Measure voltage between "E23-24" terminal of ECM
connector and engine ground.
Is voltage 10 – 14 V?
10 Fuel level sensor ground circuit check
1) Disconnect connector from sub fuel lever sensor with
ignition switch turned OFF.
2) Measure resistance between "BLK/YEL" wire terminal of
fuel pump connector and vehicle body ground.
Is resistance below 5
11 High resistance circuit check for fuel level sensor circuit
1) Disconnect connectors from ECM.
2) Measure resistance between "YEL/RED" wire terminal of
fuel pump connector and "E23-24" wire terminal of ECM
connector.
Is resistance below 5
12 Fuel level sensor check
1) Check fuel level sensor (main and sub) referring to "Fuel
Level Sensor Inspection: in Section 9C".
Is it in good condition?
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Action
Ω
?
Ω
?
www.CarGarage.ir
Yes
Go to Step 8.
Go to Step 10.
"YEL/RED" wire is open
circuit.
Go to Step 11.
Go to Step 12.
"YEL/GRN" wire
between main fuel lever
sensor and sub fuel
lever sensor is open or
high resistance. If wire
is OK, substitute a
known-good ECM and
recheck.
No
"YEL/RED" wire shorted
to other circuit.
Go to Step 9.
Substitute a known-
good ECM and recheck.
"BLK/YEL" wire in open
or high resistance
circuit.
"YEL/RED" wire is high
resistance circuit.
Faulty fuel level sensor.