AT OIL TEMP Warning Light Display: Inspection

Diagnosis: 

• 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 TCM. 

   Check 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 TCM. 

   Check 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. 

   Check the 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. 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 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 Subaru Select 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.

   Is the display 125°C or more?

   • Yes  : Go to 9. 
   • No  : Check the 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 procedure. 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 after the ATF temperature lowers.