Diagnostic Instructions
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 lower control valve body. The SS valve 2 is a normally closed (NC) solenoid valve and controls fluid to the clutch select valve 3 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 first gear engine braking, if first gear ratio is not achieved in a predetermined period of time, the TCM commands second gear
and if second gear ratio is attained this indicates a stuck OFF SS valve 2 and the DTC will set.
Conditions for Running the DTC
| • | Active the ignition voltage. |
| • | Active the high side driver |
| • | Calculated throttle position is equal to or greater than 10 percent. |
| • | Engine torque is between 120-1,492 N·m (89-1,100 lb ft). |
| • | Transmission Fluid Temperature (TFT) is equal to or greater than 0°C (32°F). |
Conditions for Setting the DTC
| • | The TCM detects second gear ratio is achieved. |
| • | Fail Case 1 and Fail Case 2 must occur in sequential order. |
Fail Case 1
Commanded gear equals first lock or first freewheel and gearbox slip is equal to or greater than 100 RPM. The above conditions exist for more than 5 seconds.
Fail Case 2
Commanded gear equals second gear and second gear box slip is less than or equal to 35 RPM or gear box slip is equal to or less than 100 RPM and shift time-out occurs and PC Sol 4 commanded pressure is at maximum. The above condition
occurs for no more than 4 seconds.
Action Taken When the DTC Sets
DTC P0756 is a Type A DTC.
Conditions for Clearing the DTC
DTC P0756 is a Type A 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
DTC Type Reference
Electrical Information Reference
Special Tools
DT-47825 Control Solenoid Test Plate
Circuit/System Verification
- Perform the
Transmission Fluid Check.
- Operate the vehicle in drive with the calculated throttle position greater than 15 percent to obtain 56 km/h (35 mph) 2 times.
| ⇒ | If the DTC resets, go to Circuit/System Testing. |
Circuit/System Testing
- Perform the
Line Pressure Check.
| ⇒ | If the pressure is out of specification correct that concern first. |
- Perform the
Control Solenoid Valve and Transmission Control Module Assembly Cleaning and retest the DTC as outlined in the Circuit/System Verification steps.
| ⇒ | If the DTC resets, continue on with testing. |
- Perform the
Control Solenoid Valve and Transmission Control Module Assembly Inspection.
| ⇒ | If a concern is found, repair or replace the control solenoid (w/body and TCM) valve assembly. |
- Perform the
Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test.
| ⇒ | If the solenoid is found to be leaking or stuck OFF, replace the control solenoid (w/body and TCM) valve assembly. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
