DTC P2757: Torque Converter Clutch Pressure Control Solenoid Control Circuit Performance/Stuck Off: Notes
1. -
DTC detecting condition:
Detected when two consecutive driving cycles with fault occur.
Trouble symptom:
No lock-up occurs.
Wiring diagram:
CVT control system Ref. to WIRING SYSTEM>CVT CONTROL SYSTEM .
- Use CHECK BOARD when measuring the TCM terminal voltage and resistance.
- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. Ref. to TRANSMISSION (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .
- CHECK DTC
.
Read the DTC using Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
Is a DTC other than DTC P2757 displayed?
Yes : Perform the diagnosis according to DTCs other than P2757. Ref. to TRANSMISSION (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST .
No : Go to 2 .
- CHECK LOCK-UP DUTY SOLENOID (ACTIVE TEST)
.
- Turn the ignition switch to ON.
- Using the Subaru Select Monitor, perform the active test of the lock-up duty solenoid. Ref. to TRANSMISSION (DIAGNOSTICS)>ACTIVE TEST .
Does the indication of 0 - 50% appear repeatedly during the active test, and does operating sound emit during indicating 50%?
Yes : Go to 6 .
No : Go to 3 .
- CHECK LOCK-UP DUTY SOLENOID
.
- Turn the ignition switch to OFF.
- Disconnect the TCM connector.
- Measure the resistance between TCM connector and transmission body.
Connector & terminal
(T10) No. 15 - Transmission body:
Is the resistance approximately 10 - 14.2 Ω? (When cold)
Yes : Replace the control valve body. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CONTROL VALVE BODY .
No : Go to 4 .
- CHECK HARNESS
.CAUTION: Start work after ATF cools down.
- Remove the transmission valve cover.
- Disconnect the control valve body connector.
- Measure the resistance between TCM connector and control valve body connector.
Connector & terminal
(T10) No. 15 - (T11) No. 9:
Is the resistance less than 1 Ω?
Yes : Go to 5 .
No : Repair the open circuit of harness.
- CHECK HARNESS
.
Measure the resistance between TCM connector and transmission body.
Connector & terminal
(T10) No. 15 - Control valve body:
Is the resistance 1 MΩ or more?
Yes : Replace the control valve body. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CONTROL VALVE BODY .
No : Repair the short circuit of harness.
- CHECK TRANSMISSION FLUID
.
- Connect all connectors.
- Check the amount of ATF. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CVTF>INSPECTION .
Is the check result OK?
Yes : Go to 7 .
No : Adjust the amount of ATF.
- CHECK TRANSMISSION FLUID
.
Check the condition of ATF. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CVTF>REPLACEMENT .
Is the check result OK?
Yes : Return ATF. Go to 8 .
No : Check according to the "Corrective action" of ATF (CVTF) "CONDITION CHECK". Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CVTF>REPLACEMENT .
- 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).
- Depress the brake pedal, and shift the select lever to "D" range.
- Shift the select lever to "P" range.
- Stabilize the engine speed at idle.
- Read the data of [Actual Secondary Pressure] using Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DATA MONITOR .
Is [Actual Secondary Pressure] 0.5 - 1.5 MPa?
Yes : Replace the control valve body Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CONTROL VALVE BODY .
Go to 9 .
No : Perform the diagnosis according to DTC P0841. Ref. to TRANSMISSION (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC P0841: TRANSMISSION FLUID PRESSURE SENSOR/SWITCH "A" CIRCUIT RANGE/PERFORMANCE .
- DRIVING CHECK FOR LOCK-UP CONDITION
.
- Using the Subaru Select Monitor, perform the clear memory. Ref. to COMMON (DIAG)>CLEAR MEMORY .
- Turn the ignition switch to OFF.
- Start the engine.
- Warm up until the ATF temperature exceeds 50°C.
- Display the data of [Lock Up Duty Ratio] and [Front Wheel Speed] using Subaru Select Monitor.
Ref. to TRANSMISSION (DIAGNOSTICS)>DATA MONITOR .
- Drive the vehicle for one minute or more while keeping such constant speed that [Lock Up Duty Ratio] is 70% or more, and [Front Wheel Speed] is 40 km/h (25 MPH) or more.
- Turn the ignition switch to OFF.
- Start the engine.
- Perform the procedure in step 6) again.
- Read the DTC using Subaru Select Monitor. Ref. to TRANSMISSION (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
Does the AT OIL TEMP light blink and is DTC P2757 displayed?
Yes : Replace the torque converter assembly. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>TORQUE CONVERTER .
No : Current condition is normal. It is possible that temporary poor contact occurs.