Diagnostic Instructions
DTC Descriptor
DTC P1751: Shift Valve 1 Performance
Circuit/System Description
The shift valve 1 (clutch select valve 2) is part of the lower control valve body. The shift valve 1 (clutch select valve 2) controls fluid to the R1 and 4-5-6 clutches. During this diagnostic test, intrusive actions are taken
by the transmission control module (TCM) to test the clutch select valve 2 to see if the valve is stuck. The TCM commands the shift solenoid (SS) 1 ON to put pressure on the valve towards the spring and at the same time, elevates line pressure
slightly to assist the spring side pressure. If the spring is broken, the valve will slip back towards the spring indicating a mechanical failure and the DTC will set.
Conditions for Running the DTC
| • | No DTCs P0716 or P0717. |
| • | No DTCs P0722 or P0723. |
| • | No DTCs P2763, P2763, or P2764. |
| • | No DTCs P0741 or P0742. |
| • | The engine run time is greater than 5 seconds. |
| • | The transmission fluid temperature (TFT) is 20-130°C (68-266°F). |
| • | The calculated throttle position is between 8-90 percent. |
| • | The engine torque is greater than 50 N·m (36 lb. ft). |
| • | No upshift or downshift in process. |
| • | DTC P0742 has not passed or failed for this torque converter clutch (TCC) cycle. |
| • | The attained gear slip is equal to or greater than 70 RPM. |
Conditions for Setting the DTC
The TCM detects attained gear slip greater than 75 RPM for 0.5 seconds.
Action Taken When the DTC Sets
DTC P1751 is a Type B DTC.
Conditions for Clearing the DTC
DTC P1751 is a Type B DTC.
Diagnostic Aids
When attempting to set transmission performance DTCs, observe the Freeze Frame and Failure Records to assist in duplicating the failure conditions. Ensure the transmission fluid level is correct and there are no leaks.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Circuit/System Verification
Operate the vehicle in drive with the calculated throttle position greater than 8 percent and make sure the TCC is commanded ON and OFF a minimum of 5 times.
If the DTC resets, go to Component Testing.
Component Testing
Inspect the lower control valve body for a stuck clutch select valve 2, a broken clutch select valve 2 spring, debris or damage.
If you found a valve body concern, repair or replace the lower control valve body as necessary.
Repair Instructions
Important: Always perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
Replace the control valve body. Refer to
Control Valve Lower Body and Upper Body Replacement.
