Automatic Transmission - 2MT70

DTC P0796 or P0797

Diagnostic Instructions

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

DTC Descriptors
DTC P0796
- Pressure Control (PC) Solenoid 3 - Stuck Off

DTC P0797
- Pressure Control (PC) Solenoid 3 - Stuck On

Circuit/System Description

The clutch pressure control (PC) solenoid 3 is part of the control solenoid (w/body and TCM) valve assembly and is not serviced separately. The transmission control module (TCM) supplies 12 volts to the clutch PC solenoid 3 on the high side driver 1 circuit. The TCM controls the PC solenoid 3 through the clutch PC solenoid 3 control circuit. The normally high clutch PC solenoid 3 controls fluid to the following valves:

* Variable low 1-2 reverse and 4th clutch valve
* Shift solenoid valve mode - B

Conditions for Running the DTC

P0796 or P0797
* The engine run time is greater than 1 second.
* SS valve 1 is not in a transition state.
* The transmission line pressure is greater than 370 kpa (54 psi) and not fluctuating by greater than 30 kpa (4 psi).
* Propulsion is active.

P0796

The clutch PC solenoid 3 commanded pressure is greater than 1800 kpa (261 psi) for 4.5 seconds.

P0797

The clutch PC solenoid 3 commanded pressure is less than 5 kpa (1 psi) for 4.5 seconds.

Conditions for Setting the DTC

P0796 - Fail Case 1

The clutch PC solenoid 3 commanded pressure is 1800 kpa (261 psi) and the TFP switch 3 state is Low for 36 seconds.

P0796 - Fail Case 2

The clutch PC solenoid 3 commanded pressure is 1800 kpa (261 psi) and the TFP switch 3 state is Low for 200 milliseconds greater than 5 times during a key cycle.

P0797 - Fail Case 1

The clutch PC solenoid 3 commanded pressure is 5 kpa (1 psi) and the TFP switch 3 state is High for 36 seconds.

P0797 - Fail Case 2

The clutch PC solenoid 3 commanded pressure is 5 kpa (1 psi) and the TFP switch 3 state is High for 1.25 seconds greater than 5 times during a key cycle.

Action Taken When the DTC Sets

* P0796 and P0797 are Type B DTCs.
* The TCM commands maximum line pressure.
* The TCM freezes transmission adaptive functions.

Conditions for Clearing the DTC

P0796 and P0797 are Type B DTCs.

Diagnostic Aids

When attempting to set transmission performance DTCs, observe the Freeze Frame and Failure Records to assist in duplicating the failure conditions.

Reference Information
Schematic Reference

Automatic Transmission Controls Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference

Control Module References (Programming and Relearning) 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.

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

2. Perform the Transmission Fluid Check (Transmission Fluid Check).
3. Turn ON the ignition, with the engine OFF.

Note: Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records.

4. Record the DTC Freeze Frame and Failure Records.
5. Clear the DTC.
6. Perform the Transmission Fluid Check (Transmission Fluid Check) to verify correct fluid level and condition. The transmission fluid level should be within the crosshatch band and the transmission fluid should be red or dark brown.

• If the transmission fluid is low or discolored, refer to Transmission Fluid Replacement (Removal and Replacement).

7. Engine idling at operating temperature. Attempt to clean or free up a potential sticking valve with the scan tool Service Cleaning Procedure. Refer to Control Solenoid Valve and Transmission Control Module Assembly Cleaning (Control Solenoid Valve and Transmission Control Module Assembly Cleaning) for further instructions.
8. Operate the vehicle in DRIVE to obtain 72 km/h (45 mph) and achieve 4th gear, stop the vehicle, turn the ignition Off for at least 30 seconds. Perform this 2 times.

• If the DTC resets, go to Circuit/System Testing.

Circuit/System Testing

1. Perform the Line Pressure Check (Line Pressure Check).

• If the pressure is out of specification, correct this concern first.

2. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (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.

3. 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 clutch PC solenoid 3 is found to be leaking or stuck closed, replace the control solenoid (w/body and TCM) valve assembly.

4. Inspect the control valve lower body assembly for sticking valves, damage, scored bores, or debris.

• If a concern if found in the valve body, repair or replace the valve body as necessary.

Component Testing

1. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (Control Solenoid Valve and Transmission Control Module Assembly Inspection).
2. Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test (Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test).

Repair Instructions

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

* Control Valve Lower Body and Upper Body Replacement (2MT70 - Automatic Transmission).
* Control Module References (Programming and Relearning) for control solenoid (w/body and TCM) valve assembly replacement, setup, and programming.