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Home >> Suzuki >> 2009 >> Grand Vitara Base, Standard >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 12 (Engine Cooling System (N32A)) >> Diagnostic Information and Procedures >> Radiator Cooling Fan Low, Mid and High Speed Control System Check >> Troubleshooting
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Radiator Cooling Fan Low, Mid and High Speed Control System Check: Troubleshooting

WARNING: This page is about a different variant/trim than selected.
WARNING: Keep hands, tools, and clothing away from radiator cooling fan to prevent personal injury. This fan is driven by electric motors that can turn on whether or not the engine is running. The fan motor can start automatically in response to the ECT sensor signal if ignition switch is at "ON" position.
NOTE:
  • Radiator cooling fan low speed control takes place as follows: If engine coolant temperature becomes 102 °C or higher with engine at idle, radiator fan relay No. 1 turns on and then radiator fan motor No. 1 and No. 2 run at low speed. When the coolant temperature becomes 99 °C or lower, both fan motors stop operating.
  • Radiator cooling fan mid and high speed control takes place as follows: If engine coolant temperature becomes 106.5 °C or higher with engine at idle, radiator fan relay No. 3 turns on and then radiator fan motor No. 1 runs at high speed. With delay of 0.3 second after start of radiator fan motor No. 1, radiator fan relay No. 2 turns on and then radiator fan motor No. 2 runs at high speed. When engine coolant temperature drops to 103.5 °C or lower, high speed control is switched to low speed control.
  • Before performed troubleshooting, be sure to read PRECAUTIONS OF ECM CIRCUIT INSPECTION .
  • When measuring circuit voltage, resistance and/or pulse signal at ECM connector, connect special tool between ECM and ECM connectors. See INSPECTION OF ECM AND ITS CIRCUITS .
TROUBLESHOOTING CHART

Step Action YES NO
1  DTC check 
  1. With ignition switch OFF, connect SUZUKI scan tool to DLC.
  2. With ignition switch ON, check DTC.

Is DTC detected? 		 Go to troubleshooting for applicable DTC and recheck. Go to Step 2.
2  Radiator cooling fan low speed control circuit check 
  1. Check radiator cooling fan when it starts operating at low speed. See RADIATOR COOLING FAN ASSEMBLY ON-VEHICLE INSPECTION .

Is it in good condition? 		 Go to Step 3. Go to Step 6.
3  Radiator cooling fan mid and high speed control circuit check 
  1. Check radiator cooling fan when it starts operating at mid and high speed. See RADIATOR COOLING FAN ASSEMBLY ON-VEHICLE INSPECTION .

Is it in good condition? 		 Radiator cooling fan control circuits are in good condition. Go to Step 4.
4  Radiator cooling fan relay No. 2 power supply circuit (contact side) check 
  1. With ignition switch OFF, disconnect radiator cooling fan relay No. 2 from fuse box.
  2. Check radiator cooling fan relay No. 2 for proper terminal connections.
  3. If terminal connections are OK, turn ignition switch to ON position.
  4. Check that voltage between radiator cooling fan relay No. 2 power supply circuit (contact side) (C1) and vehicle body ground is battery voltage.

Is voltage OK? 		 Go to Step 5. Repair or replace defective wire harness.
5  Radiator cooling fan relay No. 3 ground circuit check 
  1. Check radiator cooling fan relay No. 3 for proper terminal connections.
  2. If connections are OK, check that wiring harness resistance between radiator cooling fan relay No. 3 ground circuit (B2) and vehicle body ground is less than 3 Ω.

Is resistance OK? 		 Go to Step 6. Repair or replace defective wire harness.
6  Radiator cooling fan relay No. 1 power supply circuit (contact side) check 
  1. Disconnect radiator cooling fan relay No. 1 from fuse box.
  2. Check radiator cooling fan relay No. 1 for proper terminal connections.
  3. If connections are OK, check that voltage between radiator cooling fan relay No. 1 power supply circuit (contact side) (A1) and vehicle body ground is battery voltage.

Is voltage OK? 		 Go to Step 7. Repair or replace defective wire harness.
7  Radiator cooling fan relay No. 1, No. 2 and No. 3 check 
  1. With ignition switch OFF, check radiator cooling fan relays No. 1, No. 2 and No. 3. See RADIATOR COOLING FAN RELAY INSPECTION .

Are they in good condition? 		 Go to Step 8. Replace radiator cooling fan relays No. 1, No. 2 and No. 3.
8  Radiator cooling fan motor No. 1 drive circuit check 
  1. Disconnect radiator cooling fan motor No. 1 connector.
  2. Check radiator cooling fan motor No. 1 for proper terminal connections.
  3. If connections are OK, check that radiator cooling fan motor No. 1 drive circuit (A2) is as follows.
    • Wiring harness resistance of radiator cooling fan motor No. 1 drive circuit is less than 3 Ω.
    • Insulation resistance is infinity between radiator cooling fan motor No. 1 drive circuit and vehicle body ground.
    • Circuit voltage of radiator cooling fan motor No. 1 drive circuit is 0 - 1 V with ignition switch turned ON.

Is it in good condition? 		 Go to Step 9. Repair or replace defective wire harness.
9  Radiator cooling fan relay No. 3 power supply circuit (contact side) check 
  1. With ignition switch OFF, check that radiator cooling fan relay No. 3 power supply circuit (contact side) (B1) is as follows.
    • Wiring harness resistance of radiator cooling fan relay No. 3 power supply circuit (contact side) is less than 3 Ω.
    • Insulation resistance is infinity between radiator cooling fan relay No. 3 power supply circuit (contact side) and vehicle body ground.
    • Circuit voltage of radiator cooling fan relay No. 3 power supply circuit (contact side) is 0 - 1 V with ignition switch turned ON.

Is it in good condition? 		 Go to Step 10. Repair or replace defective wire harness.
10  Radiator cooling fan relay No. 2 drive circuit (contact side) check 
  1. With ignition switch OFF, disconnect radiator cooling fan motor No. 2 connector.
  2. Check radiator cooling fan motor No. 2 for proper terminal connections.
  3. If connections are OK, check that radiator cooling fan relay No. 2 drive circuit (contact side) (C2) is as follows.
    • Wiring harness resistance of radiator cooling fan relay No. 2 drive circuit (contact side) is less than 3 Ω.
    • Insulation resistance is infinity between radiator cooling fan relay No. 2 drive circuit (contact side) and vehicle body ground.
    • Circuit voltage of radiator cooling fan relay No. 2 drive circuit (contact side) is 0 - 1 V with ignition switch turned ON.

Is it in good condition? 		 Go to Step 11. Repair or replace defective wire harness.
11  Radiator cooling fan motor No. 2 ground circuit check 
  1. Check that wiring harness resistance between radiator cooling fan motor No. 2 ground circuit (C3) and vehicle body ground is less than 3 Ω.

Is resistance OK? 		 Go to Step 12. Repair or replace defective wire harness.
12  Radiator cooling fan motor No. 1 and No. 2 check 
  1. Check radiator cooling fan motors No. 1 and No. 2. See RADIATOR COOLING FAN ASSEMBLY ON-VEHICLE INSPECTION .

Are they in good condition? 		 Substitute a known-good ECM and recheck. See ENGINE CONTROL MODULE (ECM) REMOVAL AND INSTALLATION . Replace radiator cooling fan motor No. 1 and/or No. 2. See RADIATOR COOLING FAN ASSEMBLY REMOVAL AND INSTALLATION .
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