Basic Diagnostic Procedure: Procedure

WARNING: This page is about a different car, the 2022 Subaru WRX. However, it is still accessible from the selected car via links, so may be relevant.

CHECK PRE-INSPECTION .
1. Ask the customer when and how the trouble occurred using the Check List for Interview. Ref. to TRANSMISSION (DIAGNOSTICS)>CHECK LIST FOR INTERVIEW
2. Before performing diagnostics, check the following items which might affect CVT problems.
  - General inspection Ref. to TRANSMISSION (DIAGNOSTICS)>GENERAL DESCRIPTION>INSPECTION
  - Disconnection of harness connector
  - Visual check for harness damage
  - Oil leakage
  - Stall test Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>STALL TEST
  - Secondary pressure test Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>SECONDARY PRESSURE TEST
  - Line pressure test Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>LINE PRESSURE TEST
  - Transfer clutch pressure test Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>TRANSFER CLUTCH PRESSURE TEST
  - Time lag test Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>TIME LAG TEST
  - Road test Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>ROAD TEST
  - Inhibitor switch Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>INHIBITOR SWITCH
Is the check result OK?

Yes : Go to 2.

No : Repair the items which may be affecting the CVT trouble.
CHECK AT OIL TEMP LIGHT .
Start the engine and wait for 2 seconds or more.

Does the AT OIL TEMP light blink?

Yes : Go to 3.

No : Go to 4.
CHECK DTC .
Read the DTC of [Transmission] using the Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)

NOTE:
If the communication function of the Subaru Select Monitor cannot be executed properly, check the communication circuit. Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC PROCEDURE FOR SUBARU SELECT MONITOR COMMUNICATION

Are any DTCs displayed?

Yes : Record the DTC, time stamp and freeze frame data. Go to 5.

No : Go to 4.
PERFORM GENERAL DIAGNOSTICS .
1. Inspect using "Diagnostic Procedure without Diagnostic Trouble Code (DTC)". Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC PROCEDURE WITHOUT DIAGNOSTIC TROUBLE CODE (DTC)
2. Inspect using "Diagnostics with Phenomenon". Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTICS WITH PHENOMENON
3. Perform the road test. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>ROAD TEST
4. Read the DTC of [Transmission] using the Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)
Are any DTCs displayed?

Yes : Go to 5.

No : Finish the diagnosis.
PERFORM DIAGNOSIS .
1. Inspect by referring to "Diagnostic Procedure with Diagnostic Trouble Code (DTC)". Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
  NOTE:
  For the DTC table, refer to "Diagnostic Trouble Code (DTC)". Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST
2. Repair or replace the cause of trouble.
3. Using the Subaru Select Monitor, perform the clear memory of [Transmission]. Ref. to COMMON (DIAGNOSTICS)>CLEAR MEMORY
4. Execute the inspection mode. Ref. to TRANSMISSION (DIAGNOSTICS)>INSPECTION MODE
5. Check the readiness code of [Transmission] using Subaru Select Monitor and confirm that the diagnosis is completed. Ref. to TRANSMISSION (DIAGNOSTICS)>ALL READINESS DIAGNOSTIC CODE(S)
6. Read the DTC of [Transmission] using the Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)
Are any DTCs displayed?

Yes : Inspect by referring to "Diagnostic Procedure with Diagnostic Trouble Code (DTC)". Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)

No : Finish the diagnosis.