GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    â€¢ Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    â€¢ Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    â€¢  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 (SS) valve 2 is part of the control solenoid (w/body and TCM) valve assembly and is not serviced separately. The SS valve 2 is a normally closed (NC) 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 SS 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 SS 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.

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

    â€¢  Circuit Testing
    â€¢  Connector Repairs
    â€¢  Testing for Intermittent Conditions and Poor Connections
    â€¢  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information.

Special Tools

DT-47825 Control Solenoid Test Plate Kit

Circuit/System Verification

  1. Verify that DTCs P0721, P0722, P0723, P0966, P0967, P0969, P0970, P0971, P0973, P0974, P0976, P0977, P2720, P2721, P2728, P2729, or P2730 are not set.
  2. ⇒ If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
  3. Perform the Transmission Fluid Check .
  4. Operate the vehicle in drive to obtain 56 km/h (35 mph), stop the vehicle, turn the ignition Off for at least 30 seconds. Perform this 2 times.
  5. ⇒If the DTC resets, go to Circuit/System Testing.

Circuit/System Testing

  1. Perform the Line Pressure Check .
  2. ⇒If the pressure is out of specification correct that concern first.
  3. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection .
  4. ⇒If a concern is found, repair or replace the control solenoid (w/body and TCM) valve assembly.
  5. Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test .
  6. ⇒If the solenoid is found to be leaking or stuck OFF, replace the control solenoid (w/body and TCM) valve assembly.
    ⇒ If the control solenoid (w/body and TCM) valve assembly tests normal, inspect the valve body and hydraulic circuits for a leak or a stuck valve.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for control solenoid (w/body and TCM) valve assembly replacement, setup, and programming.