Radiator Cooling Fan Control System Check: Troubleshooting

WARNING: Keep hands, tools, and clothing away from radiator cooling fan to prevent personal injury. This fan is driven by electric motor that can turn on whether or not the engine is running. The fan motor can start automatically in response to ECT sensor signal if ignition switch is at "ON" position.

NOTE:

For details about engine cooling fan operation, refer to "COOLING FAN OPERATION DESCRIPTION ":
Before beginning troubleshooting, be sure to read PRECAUTIONS FOR ECM CIRCUIT INSPECTION .
When measuring circuit voltage, resistance and/or pulse signal of ECM.

DIAGNOSTIC INFORMATION AND PROCEDURES REFERENCE CHART

Step	Action	YES	NO
1	DTC Check Turn OFF ignition switch and connect SUZUKI scan tool to DLC. Turn ignition switch to ON position and check DTC. Is there DTC(s)?	Go to applicable DTC troubleshooting and recheck.	Go to Step 2.
2	Radiator cooling fan low mode control check Check radiator cooling fan control for low mode. See Radiator Cooling Fan Assembly On-Vehicle Inspection Is it in good condition?	Go to Step 3.	Go to Step 4.
3	Radiator cooling fan high mode control check Check radiator cooling fan control for high mode. See Radiator Cooling Fan Assembly On-Vehicle Inspection Is it in good condition?	Radiator cooling fan control system is in good condition.	Go to Step 8.
4	Radiator cooling fan relay No. 1 power supply circuit (switch side) check Turn OFF ignition switch and remove radiator cooling fan relay No. 1 from relay box No. 1. Check for proper connection to radiator cooling fan relay No. 1 at each terminal. If OK, measure voltage between radiator cooling fan relay No. 1 power supply circuit (A1) and vehicle body ground. Is it 10 - 14 V?	Go to Step 5.	Repair or replace radiator cooling fan relay No. 1 power supply circuit (switch side).
5	Radiator cooling fan relay No. 1 check Check radiator cooling fan relay No. 1. See Radiator Cooling Fan Relay Inspection Is it in good condition?	Go to Step 6.	Replace radiator cooling fan relay No. 1.
6	Radiator cooling fan motor drive circuit (low speed) check Turn OFF ignition switch and disconnect radiator cooling fan motor connector. Check for proper connection to radiator cooling fan motor at each terminal. If OK, check that radiator cooling fan motor drive circuit (low speed) (B1) is in the following conditions. Wiring harness resistance of radiator cooling fan motor drive circuit (low speed) is less than 3 Ω or less. Insulation resistance between radiator cooling fan drive circuit (low speed) and vehicle body ground is infinity. Circuit voltage of radiator cooling fan motor drive circuit (low speed) is 0 - 1 V with ignition switch in ON position. Are they in good condition?	Go to Step 7.	Repair or replace radiator cooling fan motor drive circuit (low speed).
7	Radiator cooling fan motor ground circuit check Measure resistance between radiator cooling fan motor ground circuit (C1) and vehicle body ground. Is resistance 3 Ω or less?	Go to Step 14.	Repair or replace radiator cooling fan motor ground circuit.
8	Radiator cooling fan relay No. 2 power supply circuit (switch side) check Turn OFF ignition switch and remove radiator cooling fan relay No. 2 from relay box No. 1. Check for proper connection to radiator cooling fan relay No. 2 at each terminal. If OK, measure voltage between radiator cooling fan relay No. 2 power supply circuit (A2) and vehicle body ground. Is it 10 - 14 V?	Go to Step 9.	Repair or replace radiator cooling fan relay No. 2 power supply circuit (switch side).
9	Radiator cooling fan relay No. 2 check Check radiator cooling fan relay No. 2. See Radiator Cooling Fan Relay Inspection Is it in good condition?	Go to Step 10.	Replace radiator cooling fan relay No. 2.
10	Radiator cooling fan motor drive circuit (high speed) check Turn OFF ignition switch and disconnect radiator cooling fan motor connector. Check for proper connection to radiator cooling motor at each terminal. If OK, check that radiator cooling motor drive circuit (high speed) (B2) is in the following conditions. Wiring harness resistance of radiator cooling fan motor drive circuit (high speed) is 3 Ω or less. Insulation resistance between radiator cooling fan motor drive circuit (high speed) and vehicle body ground is infinity. Circuit voltage of radiator cooling fan motor drive circuit (high speed) is 0 - 1 V with ignition switch in ON position. Is it in good condition?	Go to Step 11.	Repair or replace cooling motor drive circuit (high speed).
11	Radiator cooling fan relay No. 3 power supply circuit (switch side) check Check that radiator cooling fan relay No. 3 power supply circuit (switch side) (A3) is in the following conditions. Wiring harness resistance of radiator cooling fan relay No. 3 power supply circuit (switch side) is 3 Ω or less. Insulation resistance between radiator cooling fan relay No. 3 power supply circuit (switch side) and vehicle body ground is infinity. Circuit voltage of radiator cooling fan relay No. 3 power supply circuit (switch side) is 0 - 1 V with ignition switch in ON position. Is it in good condition?	Go to Step 12.	Repair or replace radiator cooling fan relay No. 3 power supply circuit (switch side).
12	Radiator cooling fan relay No. 3 check Check radiator cooling fan relay No. 3. See Radiator Cooling Fan Relay Inspection Is it in good condition?	Go to Step 13.	Replace radiator cooling fan relay No. 3.
13	Radiator cooling fan relay No. 3 ground circuit check Measure resistance between radiator cooling fan motor ground circuit (C2) and vehicle body ground. Is resistance 3 Ω or less?	Go to Step 14.	Repair or replace cooling fan relay No. 3 ground circuit.
14	Radiator cooling fan motor check Check radiator cooling fan motor. Is it in good condition?	Substitute a known-good ECM and recheck.	Replace radiator cooling fan motor.