2ML70 - Automatic Transmission

DTC P0751

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions)provides an overview of each diagnostic category.

DTC Descriptor
DTC P0751
- Shift Solenoid (SS) 1 Valve Performance - Stuck Off

Circuit/System Description

The shift solenoid 1 and transmission control module (TCM) are part of the control solenoid valve assembly and are not serviced separately. The TCM supplies 12 V to shift solenoid 1 on the high side driver 1 circuit. The TCM controls the normally closed shift solenoid 1 on the shift solenoid 1 control circuit. The shift solenoid 1 controls the transmission fluid to the 1-3 clutch regulator valve assembly.

Conditions for Running the DTC

EVT 2, gear 3, or gear 4 is commanded.

Conditions for Setting the DTC

The TCM detects shift solenoid valve 1 is OFF when commanded ON.

Action Taken When the DTC Sets

P0751 is a Type A DTC.

Conditions for Clearing the DTC

P0751 is a Type A DTC.

Reference Information
DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)

Circuit/System Verification

1. Verify that P0721, P0722, P0723, P0966, P0967, P0969, P0970, P0971, P0973, P0974, P0976, P0977, P2720, P2721, P2728, P2729, or P2730 is not set.

• If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle).

2. Perform the Transmission Fluid Level and Condition Check (Transmission Fluid Level and Condition Check).
3. Perform the Line Pressure Check (Line Pressure Check).
4. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (Control Solenoid Valve and Transmission Control Module Assembly Inspection).
5. Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test (Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test).

• If the shift solenoid 1 is found to be leaking or stuck OFF, replace the Q8 control solenoid valve assembly.

• If the Q8 control solenoid valve assembly tests normal, inspect the valve body and hydraulic circuits for a leak or a stuck valve.

6. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Control Valve Upper Body Replacement (2ML70 - Automatic Transmission)for Control Valve Body repair or replacement.
* Control Module References (Control Module References) for Control Solenoid Valve Assembly replacement, programming and setup.