At Oil Temp Warning Light Display: Diagnosis

Detecting condition: 

• CAN communication is lost with the combination meter.
• Combination meter malfunction
• TCM is in special control mode.
• AT learning is not finished.

Trouble symptom: 

• When the ignition switch is turned to ON, the AT OIL TEMP light does not illuminate.
• AT OIL TEMP light remains lit after engine start.

1. CHECK DTC  .

   Read the DTC of [Transmission] using the Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is DTC U0155 or U0423 displayed?

   Yes  : Perform the self-diagnosis of combination meter. Ref. to INSTRUMENTATION/DRIVER INFO>COMBINATION METER SYSTEM>OPERATION>SELF-DIAGNOSIS DISPLAY MODE .

   No  : Go to  2 .

2. CHECK DTC  .

   Read the DTC of [Transmission] using the Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Are DTCs other than U0155 and U0423 displayed?

   Yes  : Perform the diagnosis according to the DTC. Ref. to TRANSMISSION (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST .

   No  : Go to  3 .

3. CHECK COMBINATION METER  .

   Read the DTC of [Combination Meter] using the Subaru Select Monitor. Ref. to COMBINATION METER (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Are any DTCs displayed?

   Yes  : Perform the diagnosis according to the DTC. Ref. to COMBINATION METER (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

   No  : Go to  4 .

4. CHECK AT OIL TEMP LIGHT  .

   Turn the ignition switch to ON.

   Does AT OIL TEMP light illuminate and then go off in 2 seconds?

   Yes  : Go to  5 .

   No  : Perform the self-diagnosis of combination meter. Ref. to INSTRUMENTATION/DRIVER INFO>COMBINATION METER SYSTEM>OPERATION>SELF-DIAGNOSIS DISPLAY MODE .

5. CHECK AT OIL TEMP LIGHT  .

   Start the engine.

   Does the AT OIL TEMP light go off?

   Yes  : Current condition is normal. Go back to Basic Diagnostic Procedure. Ref. to TRANSMISSION (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .

   No  : Go to  6 .

6. CHECK DTC  .

   Read the DTC of [Transmission] using the Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Are any DTCs displayed?

   Yes  : Perform the diagnosis according to the DTC. Ref. to TRANSMISSION (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST .

   No  : Go to  7 .

7. CHECK TCM  .

   Read the data of [ATF Temperature Lamp] using Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DATA MONITOR .

   Is "ON" displayed?

   Yes  : Go to  8 .

   No  : Perform the self-diagnosis of combination meter. Ref. to INSTRUMENTATION/DRIVER INFO>COMBINATION METER SYSTEM>OPERATION>SELF-DIAGNOSIS DISPLAY MODE .

8. CHECK TCM  .

   Read the data of [ATF Temp.] using Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DATA MONITOR .

   Is the display 130°C or more?

   Yes  : Go to  9 .

   No  : Replace the TCM. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>TRANSMISSION CONTROL MODULE (TCM) .

9. CHECK ATF TEMPERATURE  .

   Check the real fluid temperature from the transmission case surface temperature.

   Does it clearly differ from the [ATF Temp.] displayed on Subaru Select Monitor?

   Yes  : Perform the diagnosis according to DTC P0712. If there is no problem, perform the diagnosis according to DTC P0713.

   No  : When ATF temperature can be judged as actually high, perform the diagnosis again after the ATF temperature lowers.