P0797
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 Descriptor
DTC P0796
- Clutch Pressure Control (PC) Solenoid 3 - Stuck Off
DTC P0797
- Clutch 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 clutch PC solenoid 3 flows fluid to the low and reverse/4-5-6 clutch when commanded OFF and exhausts fluid when commanded ON. The clutch PC solenoid 3 regulates the transmission fluid pressure to the low and reverse/4-5-6 clutch. The TCM calculates gear ratio based on data from the automatic transmission input speed sensor (ISS) and the output speed sensor (OSS). The TCM compares the known transmission gear ratio to a calculated gear ratio for each commanded gear.
Conditions for Running the DTC
P0796
* No DTCs P0716 or P0717.
* No DTCs P0722 or P0723.
* No DTCs P1825 or P1915.
* The transmission input shaft speed is greater than 60 RPM.
* Low and reverse/4-5-6 clutch is commanded ON.
P0797
* No DTCs P0716 or P0717.
* No DTCs P0722 or P0723.
* No DTCs P1825 or P1915.
* The transmission output shaft speed is greater than 200 RPM.
* Low and reverse/4-5-6 clutch is commanded OFF.
Conditions for Setting the DTC
P0776
The TCM detects an incorrect on-coming clutch gear ratio, or flare, when the low and reverse/4-5-6 clutch is commanded OFF for 0.5 seconds and the transmission input shaft speed is greater than 75 RPM from the anticipated input shaft speed.
P0797
The TCM detects an incorrect off-going clutch gear ratio, or tie-up, when the low and reverse/4-5-6 clutch is commanded ON for 0.5 seconds and the transmission input shaft speed is greater than 40 RPM from the anticipated input shaft speed.
Action Taken When the DTC Sets
* DTCs P0796 and P0797 are Type A DTCs.
* The TCM commands maximum line pressure.
* The TCM inhibits TCC.
* The TCM freezes transmission adaptive functions.
Conditions for Clearing the DIC/DTC
DTCs P0796 and P0797 are Type A 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
Circuit/System Verification
1. Perform the Transmission Fluid Check (Transmission Fluid Check) .
2. Turn ON the ignition, with the engine OFF.
Important: Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records.
3. Record the DTC Freeze Frame and Failure Records.
4. Clear the DTC.
5. Operate the vehicle in DRIVE with the calculated throttle position greater than 15% to obtain 72 km/h (45 mph) and achieve 5th gear. Perform this manoeuvre 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 Cleaning (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.
3. 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.
4. 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 solenoid is found to be leaking or stuck closed, replace the control solenoid (w/body and TCM) valve assembly.
5. 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.
6. Inspect the low and reverse/4-5-6 clutch assembly for damage.
• If a concern is found in the low and reverse/4-5-6 clutch assembly, repair or replace as necessary.
Component Testing
Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (Control Solenoid Valve and Transmission Control Module Assembly Inspection) .
Repair Instructions
Important: Always perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Control valve body replacement. Refer to Control Valve Lower Body and Upper Body Replacement (Service and Repair) .
* Low and reverse/4-5-6 clutch assembly repair or replace. Refer to Low and Reverse Clutch Overhaul (6L80) (Overhaul) and 4-5-6 Clutch Overhaul (Overhaul) in the Transmission Unit Repair Manual.
* Control solenoid (w/body and TCM) valve assembly replacement. Refer to Control Module References (Programming and Relearning) for replacement, setup, and programming.