Cooling Fan Control Inspection

1. Verify that the engine is cold.
2. Turn the ignition switch to ON.
3. Verify that the cooling fan is not operating. If the cooling fan is operating, perform as follows.




1. Connect the SSTs (NGS tester) to DLC-2.
2. Select the PID/DATA MONITOR AND RECORD function on the NGS display.
3. Using "FAN 1" and "FAN 2", verify that the cooling fan control signal is OFF.
- If the cooling fan control signal is ON, inspect the PCM terminal voltage.
- Engine coolant temperature signal

CAUTION: Connecting the wrong data link connector terminal may possibly cause a malfunction. Carefully connect the specified terminal only.




4. Using a jumper wire to turn on the test mode, perform the following
1. Short the DLC terminal TEN to body GND using a jumper wire.

5. Depress the accelerator pedal and verify that the cooling fan operates.
- If the cooling fan does not operate, proceed to next step.

6. Connect the SSTs (NGS tester).
7. Select the SIMULATION TEST function on the NGS display.

8. Turn the fan relay from OFF to ON using "FAN 1 and "FAN 2" and inspect for the cooling fan operation.
- If the cooling fan operates, inspect the PCM terminal voltage.
- Diagnostic test mode signal Closed throttle position signal
- Closed throttle position signal
- If the cooling fan does not operate, perform as follows




1. Turn the fan relay from OFF to ON using the simulation function. Operate the fan relay and inspect if the operation sound of the relay is heard.
- If the operation sound is heard, inspect the fan motor and related harness.
- If the operation sound is not heard, inspect the fan relay and related harness.