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Basic Inspection Of Radiator Fan System

  1. CHECK DTC  .

    Read the DTC using Subaru Select Monitor. Ref. to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC)>OPERATION .

    Is DTC detected?

    Yes 

    1. Repair the corresponding system.
    2. Go to  2 .

    No 

    Go to  2 .

  2. RADIATOR FAN SYSTEM OPERATION CHECK  .
    NOTE: If the radiator fans are always running, go to "INSPECTION WHEN RADIATOR FANS DO NOT STOP". Ref. to COOLING (H4DO)>Radiator Fan System>INSPECTION>INSPECTION WHEN RADIATOR FANS DO NOT STOP 
    1. Using the Subaru Select Monitor, perform the active test for the radiator fan relay. (When using the Subaru Select Monitor) Ref. to ENGINE (DIAGNOSTICS) (H4DO)>ACTIVE TEST .
    2. Install the delivery mode fuse, and turn to IG ON. (When not using the Subaru Select Monitor) Ref. to PRE-DELIVERY INSPECTION>PRE-DELIVERY INSPECTION (PDI) PROCEDURE>DELIVERY MODE .
    3. Check the radiator fan operation.

    Do the radiator main fan and sub fan rotate in the order of "OFF → Low speed revolution → High speed revolution"?

    Yes 

    System is normal.

    Restore the vehicle to its original state.

    No 

    Inspect corresponding malfunction using "Table for Diagnostics Procedure with Phenomenon".

Table for Diagnostics Procedure with Phenomenon

NOTE: If phenomenon does not match with any of the phenomenon described below, inspect fuse, relay and ground contacts for failure.
  Sub fan Main fan Sub fan Main fan Sub fan Main fan Sub fan Main fan
Stop control  Stop Stop Stop Stop Stop Stop Stop Stop
Low speed control  Stop Stop At high speed Stop At low speed At low speed At low speed At low speed
High speed control  Stop or high speed Stop or high speed At high speed Stop or high speed At high speed Stop Stop At high speed
Reference  Inspection when radiator fans do not rotate (A) Ref. to COOLING (H4DO)>Radiator Fan System>INSPECTION>INSPECTION WHEN RADIATOR FANS DO NOT ROTATE (A) . Inspection when radiator fans do not rotate (B) Ref. to COOLING (H4DO)>Radiator Fan System>INSPECTION>INSPECTION WHEN RADIATOR FANS DO NOT ROTATE>INSPECTION WHEN RADIATOR FANS DO NOT ROTATE (B) . Inspection when radiator fans do not rotate (C) Ref. to COOLING (H4DO)>Radiator Fan System>INSPECTION>INSPECTION WHEN RADIATOR FANS DO NOT ROTATE>INSPECTION WHEN RADIATOR FANS DO NOT ROTATE (C) . Inspection when radiator fans do not rotate (D) Ref. to COOLING (H4DO)>Radiator Fan System>INSPECTION>INSPECTION WHEN RADIATOR FANS DO NOT ROTATE>INSPECTION WHEN RADIATOR FANS DO NOT ROTATE (D) .