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. 10 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 POWER STEERING (DIAGNOSTICS)>Check List for Interview .

CHECK PRE-INSPECTION .
1. Ask the customer when and how the trouble occurred using the interview check list. Ref. to POWER STEERING (DIAGNOSTICS)>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 POWER STEERING (DIAGNOSTICS)>General Description>INSPECTION .
4. Save the data of [Overheating protection intervention history], [IGN count from overheating protection (most recent)], [IG Count after ECU Overheat Protection(Previous)], [IG Count after ECU Overheat Protection(Before Previous)] and Assist limit history (low voltage, high voltage) using Subaru Select Monitor. Ref. to POWER STEERING (DIAGNOSTICS)>Subaru Select Monitor>OPERATION>DATA MONITOR .
Is the check result OK?

Yes: Go to 2.

No: Repair or replace each component.
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 POWER STEERING (DIAGNOSTICS)>Subaru Select Monitor .
  NOTE: If the communication function of the Subaru Select Monitor cannot be executed properly, check the communication circuit. Ref. to POWER STEERING (DIAGNOSTICS)>Subaru Select Monitor>INSPECTION>COMMUNICATION FOR INITIALIZING IMPOSSIBLE .
Is DTC displayed?

Yes: Record the DTC, time stamp and freeze frame data. Go to 4.
NOTE:
- For the time stamp, refer to LAN service information. Ref. to LAN SYSTEM (DIAGNOSTICS)>General Description>CAUTION>TIME STAMP .
- Depending on DTCs, time stamp may not be stored.
No: Go to 3.
PERFORM GENERAL DIAGNOSTICS .
1. If the STEERING warning light is illuminated while the engine is running, clear the memory. Ref. to POWER STEERING (DIAGNOSTICS)>Clear memory .
2. Perform the Inspection Mode. Ref. to POWER STEERING (DIAGNOSTICS)>Inspection Mode .
3. Read the DTC. Ref. to POWER STEERING (DIAGNOSTICS)>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?

Yes: Finish the diagnosis.

No: Ref. to POWER STEERING (DIAGNOSTICS)>Subaru Select Monitor>INSPECTION>WITHOUT DTC .
PERFORM DIAGNOSIS .
1. Refer to "List of Diagnostic Trouble Code (DTC)". Ref. to POWER STEERING (DIAGNOSTICS)>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, clear the memory. Ref. to POWER STEERING (DIAGNOSTICS)>Clear memory .
4. Perform the Inspection Mode. Ref. to POWER STEERING (DIAGNOSTICS)>Inspection Mode .
5. Read the DTC. Ref. to POWER STEERING (DIAGNOSTICS)>Read Diagnostic Trouble Code (DTC) .
Is DTC displayed?

Yes: Repeat step 4 until DTC is not shown.

No: Finish the diagnosis.