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AT Oil Temp Warning Light Display: Inspection

WARNING: This page is about a different variant/trim than selected.

Diagnosis: 

Trouble symptom: 

  1. CHECK DTC. 

    Read the DTC relating the TCM using the Subaru Select Monitor.

    Is DTC U0155 or U0423 displayed?

    Yes:  Perform the self-diagnosis of combination meter.

    No:  Go to  2.

  2. CHECK DTC. 

    Read the DTC relating the TCM using the Subaru Select Monitor.

    Are DTCs other than U0155 and U0423 displayed?

    Yes:  Perform the diagnosis according to DTC.

    No:  Go to  3.

  3. CHECK COMBINATION METER. 

    Read DTC of combination meter.

    Are any DTCs displayed?

    Yes:  Perform the diagnosis according to DTC.

    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. Refer 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. Refer to CONTINUOUSLY VARIABLE TRANSMISSION (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .

    No:  Go to  6.

  6. CHECK DTC. 

    Read the DTC relating the TCM using the Subaru Select Monitor.

    Are any DTCs displayed?

    Yes:  Perform the diagnosis according to DTC.

    No:  Go to  7.

  7. CHECK TCM. 

    Read the data of «ATF Temperature Lamp» using the Subaru Select Monitor.

    Is "ON" displayed?

    Yes:  Go to  8.

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

  8. CHECK TCM. 

    Read the data of «ATF Temp.» using the Subaru Select Monitor.

    Is the display 125°C or more?

    Yes:  Go to  9.

    No:  Replace the TCM. Refer to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>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.