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Diagnostic Procedure

WARNING: This page is about a different car, the 2013 Subaru Forester. However, it is still accessible from the selected car via links, so may be relevant.
DIAGNOSTIC PROCEDURE

Step Check Yes No
1 CHECK HARNESS CONNECTOR BETWEEN TCM AND TRANSMISSION. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connectors from TCM and transmission.
  3. Measure the resistance of harness between TCM connector and transmission connector.

    Connector & terminal 

    (B55) No. 16 - (B11) No. 18: 

    (B55) No. 27 - (B11) No. 14: 

 Is the resistance less than 1 Ω? Go to step 2  . Repair the open circuit of harness between TCM and transmission connector, and poor contact of the connector.
2 CHECK HARNESS CONNECTOR BETWEEN TCM AND TRANSMISSION. 
Measure the resistance of harness between TCM connector and chassis ground.
Connector & terminal 
(B55) No. 16 - Chassis ground: 
(B55) No. 27 - Chassis ground: 		 Is the resistance 1 MΩ or more? Go to step 3  . Repair the short circuit of harness between TCM and chassis ground, and poor contact of connector.
3 CHECK FRONT VEHICLE SPEED SENSOR. 
Measure the resistance between transmission connector terminals.
Connector & terminal 
(T4) No. 14 - No. 18: 		 Is the resistance 450 - 650 Ω? Go to step 4  . Replace the front vehicle speed sensor. < Refer to FRONT VEHICLE SPEED SENSOR . >
4 CHECK INPUT SIGNAL FOR TCM. 
  1. Connect all connectors.
  2. Connect the Subaru Select Monitor to data link connector.
  3. Lift up the vehicle.
  4. Turn the ignition switch to ON.
  5. Run the Subaru Select Monitor.
  6. Start the engine.
  7. Slowly increase the vehicle speed to 60 km/h (37 MPH).
  8. Read the data of «Front Wheel Speed» using Subaru Select Monitor. (Compare the speedometer with Subaru Select Monitor indications.)
    NOTE: The speed difference between the front and rear wheels will illuminate the ABS warning light or VDC warning light, but this does not indicate a malfunction. If the warning light illuminates, delete the ABS or VDC memory after completing the AT control diagnosis. < Refer to CLEAR MEMORY MODE . >
 Does the speedometer indication increase as the Subaru Select Monitor data increases? Check the harness of the front vehicle speed sensor circuit, and repair the defective part. Go to step 5  .
5 CHECK FOR POOR CONTACT.  Is there poor contact of front vehicle speed sensor circuit? Repair the poor contact. Replace the TCM. < Refer to TRANSMISSION CONTROL MODULE (TCM) . >
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