DTC P0841 Secondary Oil Pressure Sensor Performance: Trouble Symptom

Acceleration is poor during standing start.
Shift control malfunction
Engine speed increases abruptly.

DIAGNOSTIC PROCEDURE

Step	Check	Yes	No
1 CHECK TRANSMISSION FLUID. Check the condition of ATF. Refer to CONDITION CHECK .	Is the ATF OK?	Go to step 2 .	Check according to the "corrective action" of ATF (CVTF) "CONDITION CHECK". Refer to CONDITION CHECK .
2 CHECK TRANSMISSION FLUID. Check the amount of ATF. Refer to ADJUSTMENT .	Is the ATF amount correct?	Go to step 3 .	Adjust the amount of ATF. Refer to ADJUSTMENT .
3 CHECK INPUT SIGNAL FOR TCM. Lift up the vehicle. Start the engine. Warm up until the ATF temperature reaches to 40 - 70°C (104 - 158°F). Shift the select lever to "P" range. Stabilize the engine speed at idle. Read the data of «Actual secondary pressure» using Subaru Select Monitor.	Is the «Actual secondary pressure» 0.5 - 1.5 MPa?	Go to step 4 .	Go to step 6 .
4 CHECK INPUT SIGNAL FOR TCM. Keep the engine speed at 3000 rpm. Read the data of «Actual secondary pressure» using Subaru Select Monitor.	Is the «Actual secondary pressure» higher than the value in Step 3? Does the value change according to the engine speed, within the range of 1.5 - 2.5 MPa?	Go to step 5 .	Go to step 6 .
5 CHECK TCM INPUT SIGNAL (STALL TEST). Apply the parking brake. Set the select lever to "D" range. Depress the brake pedal firmly. Slowly open the accelerator fully, and stabilize the engine speed. Read the data of «Actual secondary pressure» using Subaru Select Monitor.	Is the «Actual secondary pressure» higher than the value in Step 4? Does the value change according to the engine speed, within the range of 4.5 - 6.0 MPa?	Go to step 7 .	Go to step 6 .
6 CHECK SECONDARY PRESSURE SENSOR.	Is the secondary pressure sensor damaged from the standpoint of appearance?	Replace the secondary pressure sensor. Refer to SECONDARY PRESSURE SENSOR .	Perform the diagnosis according to DTC P0842, P0843 procedure.
7 DRIVING CHECK BY INSPECTION MODE. Turn the ignition switch to OFF. Perform a drive check based on the "Inspection Mode". Refer to INSPECTION MODE .	Does the AT OIL TEMP light blink and is DTC P0841 displayed?	Perform the secondary pressure test. Refer to SECONDARY PRESSURE (LINE PRESSURE) TEST .	If there is shift problems, abrupt increase of engine speed, standing start problems, replace the transmission assembly. Refer to AUTOMATIC TRANSMISSION ASSEMBLY . If it is normal, temporary poor contact occurs.