On-Vehicle Inspection

1AR-FE COOLING: COOLING FAN SYSTEM: ON-VEHICLE INSPECTION

1. CHECK COOLING FAN SYSTEM

(a) Check the input signal and output current.

HINT
Be sure to perform the inspection with an engine coolant temperature of less than 92°C (198°F).

(1) Connect the 400 A probe of an ammeter to the cooling fan motor (M+), and then the No. 2 cooling fan motor (S+) on the wire harness side.

(2) Connect the Techstream to the DLC3.

(3) Using the oscilloscope, check the waveform between terminals D61-10 (RFC) and B49-6 (E1) of the ECM.

HINT
Enter the following menus: Powertrain / Engine / Active Test / Control the Electric Cooling Fan.





Standard Waveform:





* If the input signal is abnormal, there is a malfunction in the ECM or cooling fan ECU.

* If the output current is abnormal even when the input signal is normal, there is a malfunction in the cooling fan ECU, cooling fan motor or power source circuit.