Suzuki Liana RH413, Service Manual

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1A-135 Engine General Information and Diagnosis:
Troubleshooting
Step Action Yes No
1 Is there DTC(s) ECT sensor circuit (DTC P0115) and/or
radiator fan circuit (DTC P0480)? Go to corresponding
DTC flow. Go to Step 2.
2 Check low speed radiator fan control circuit
1) Connect scan tool to DLC with ignition switch OFF.
2) Start engine and select “DATA LIST” mode on scan tool.
3) Warm up engine until coolant temp. is 97
°
C, 207
°
F or
higher and A/C switch turn OFF. (If engine coolant temp.
dose not rise, check engine cooling system or ECT
sensor.)
Is radiator cooling fan started low speed when engine
coolant temp. reached above temp.?
Go to Step 3. Perform from Step 2 to
Step 7 in DTC P0480
diag flow. If OK, Go to
Step 10.
3 Check high speed radiator fan control circuit
1) Start engine and select “DATA LIST” mode on scan tool.
2) Warm up engine until coolant temp. is 102
°
C, 216
°
F or
higher and A/C switch turn OFF. (If engine coolant temp.
dose not rise, check engine cooling system or ECT
sensor.)
Is radiator cooling fan started high speed when engine
coolant temp. reached above temp?
Radiator cooling fan
control system is in
good condition. Perform from Step 8 to
Step 13 in DTC P0480
diag flow.
If OK, Go to Step 4.
4 Check radiator fan control No.2 and No.3
1) Connect connectors to ECM with ignition switch turn
OFF.
2) Run engine until ECT is over 102
°
C, 216
°
F.
3) Measure voltage between vehicle body ground and
“G04-3” terminal wire.
Is voltage lower 1.5 V?
Go to Step 5. Faulty ECM.
5 Check radiator fan No.2 wire circuit
1) Disconnect connector from radiator fan with ignition
switch turn OFF.
2) Measure resistance between “BLU/BLK” wire and
vehicle body ground.
Is resistance infinity?
Go to Step 6. “BLU/BLK” wire shorted
to ground circuit.
6 Check radiator fan No.2 wire circuit
1) Turn ON ignition switch.
2) Measure voltage between “BLU/BLK” wire and vehicle
body ground.
Is voltage 0 V?
Go to Step 7. “BLU/BLK” wire shorted
to power supply circuit.
7 Check radiator fan control No.2
1) Connect radiator fan control relay No.2 to relay box with
ignition switch turn OFF.
2) Run engine until ECT is over 102
°
C, 216
°
F.
3) Measure voltage between vehicle body ground to “BLU/
BLK” terminal wire in disconnected harness.
Is voltage 10 – 14 V?
Go to Step 8. “BLU/BLK” or “BLU/
WHT” wire open circuit.
8 Check radiator fan No.3 wire circuit
1) Measure resistance between vehicle body ground and
“BLK” wire terminal in radiator fan No.3 connector in
relay box.
Is resistance below 1
Ω
?
Go to Step 9. “BLK” wire is open
circuit or high resistance
in circuit.