2ML70 - Automatic Transmission

DTC P0756

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 P0756
- Shift Solenoid (SS) 2 Valve Performance - Stuck Off

Circuit/System Description

The shift solenoid valve 2 is part of the control solenoid valve assembly and is not serviced separately. The shift solenoid valve 2 is a normally closed solenoid valve and controls fluid to the hybrid low, 1-2 clutch boost valve assembly and related clutches. During this diagnostic test, intrusive actions are taken by the transmission control module (TCM) to test the shift solenoid valve 2 to see if the valve is stuck OFF. When in EVT 1, gear 1, or gear 2, if the correct gear ratio is not achieved in a predetermined period of time, the TCM commands gear 3 and if gear 3 ratio is attained this indicates a stuck OFF shift solenoid valve 2 and the DTC will set.

Conditions for Running the DTC

Gear 3, 4, or EVT 2 is commanded.

Conditions for Setting the DTC

The TCM detects shift solenoid valve 2 is OFF when commanded ON.

Action Taken When the DTC Sets

P0756 is a Type B DTC.

Conditions for Clearing the DTC

P0756 is a Type B 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 2 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 Module References (Control Module References) for Q8 Control Solenoid Valve Assembly replacement, programming and setup
* Control Valve Upper Body Replacement (2ML70 - Automatic Transmission)for Control Valve Body repair or replacement.