2001 Subaru Forester BaseFACTORY OEM SERVICE PROCEDURE

Check ATF Temperature Sensor

  1. 9F1: CHECK AT OIL TEMP WARNING LIGHT. 

    CHECK: Does the AT OIL TEMP warning light remain on 2 seconds after the engine has been started? 

    1. YES:  Go to step 9F2. 
    2. NO:  Check ATF temperature sensor and combination meter circuit.
  2. 9F2: CHECK ATF TEMPERATURE SENSOR. 
    1. Read data of ATF temperature using Subaru Select Monitor.
      • ATF temperature is indicated in "°F" or "°C".
    2. Warm-up the transmission until ATF temperature is above 80°C (176°F).
      NOTE: If ambient temperature is below 0°C (32°F), drive the vehicle until the ATF reaches its operating temperature.
    3. Turn ignition switch to ON (engine OFF).

    CHECK: Does the ATF temperature change from 176°F (80°C)? 

    1. YES:  Go to step throttle position sensor, see CHECK THROTTLE POSITION SENSOR  .
    2. NO:  Check ATF temperature sensor circuit, see DTC 27: ATF TEMPERATURE SENSOR  .
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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