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Basic Diagnostic Procedure: Procedure

CAUTION:
  • The power steering control module continues to operate after the engine stops and calculate the temperature in the control module. Therefore, before starting service of the power steering system which requires disconnection of the connector, stop the engine and allow approx. 30 minutes until the control module becomes cold.
  • Before removal or installation, be sure to remove any foreign matter (dust, moisture, oil, etc.) from the power steering control module connector.
NOTE:
  • Shake the connector at the suspected trouble location to check for open or short circuits of the harness.
  • Refer to "Check List for Interview". <Ref. to CHECK LIST FOR INTERVIEW .>
Step Check Yes No
1 CHECK PRE-INSPECTION. 
  1. Ask the customer when and how the trouble occurred using the interview check list. <Ref. to CHECK LIST FOR INTERVIEW .>
  2. Check the illumination status of the STEERING warning light while the engine is running.
  3. Before performing diagnostics, check components which might affect power steering problems. <Ref. to INSPECTION , General Description.>
  4. Save the data of «Overheating protection intervention history», «IG Count after ECU Overheat Protection(latest)», «IG Count after ECU Overheat Protection(Previous)», «IG Count after ECU Overheat Protection(Before Previous)», and «Assist limited(Low voltage)» using Subaru Select Monitor. <Ref. to READ CURRENT DATA , OPERATION, Subaru Select Monitor.>
Is the check result OK? Go to step . Repair or replace each component.
2 CHECK INDICATION OF DTC. 
  1. Turn the ignition switch to OFF.
  2. Connect the Subaru Select Monitor to data link connector.
  3. Turn the ignition switch to ON and run the Subaru Select Monitor.
  4. Read the DTC using the Subaru Select Monitor. <Ref. to OPERATION , Read Diagnostic Trouble Code (DTC).>
NOTE: If the communication function of the Subaru Select Monitor cannot be executed properly, check the communication circuit. <Ref. to COMMUNICATION FOR INITIALIZING IMPOSSIBLE , INSPECTION, Subaru Select Monitor.>
Are DTC, time stamp and freeze frame data displayed? Record the DTC, time stamp and freeze frame data. Go to step .
NOTE:
  • For the time stamp, refer to LAN section. <Ref. to TIME STAMP , CAUTION, General Description.>
  • Depending on DTCs, time stamp may not be stored.
Go to step .
3 PERFORM GENERAL DIAGNOSTICS. 
  1. If the STEERING warning light is illuminated while the engine is running, perform the Clear Memory Mode. <Ref. to OPERATION , Clear Memory Mode.>
  2. Perform the Inspection Mode. <Ref. to INSPECTION MODE .>
  3. Read the DTC. <Ref. to OPERATION , Read Diagnostic Trouble Code (DTC).>
  4. Check that the DTC is not displayed.
Does the STEERING warning light illuminate at ignition switch ON, and turn off two seconds after the engine is started? Finish the diagnosis. <Ref. to WITHOUT DTC , INSPECTION, Subaru Select Monitor.>
4 PERFORM DIAGNOSIS. 
  1. Refer to "List of Diagnostic Trouble Code (DTC)". <Ref. to LIST , List of Diagnostic Trouble Code (DTC).>
  2. Correct the cause of trouble.
  3. Check the illumination status of the STEERING warning light while the engine is running, and if the warning light is lit, perform Clear Memory Mode. <Ref. to OPERATION , Clear Memory Mode.>
  4. Perform the Inspection Mode. <Ref. to INSPECTION MODE .>
  5. Read the DTC. <Ref. to OPERATION , Read Diagnostic Trouble Code (DTC).>
Is DTC displayed? Repeat step 4 until DTC is not shown. Finish the diagnosis.