6T70/6T75 - Automatic Transmission
DTC P2714 or P2715
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 Descriptors
DTC P2714
- Clutch Pressure Control (PC) Solenoid 4 - Stuck Off
DTC P2715
- Clutch Pressure Control (PC) Solenoid 4 - Stuck On
Circuit/System Description
The clutch pressure control (PC) solenoid 4 is part of the control solenoid (w/body and TCM) valve assembly and is not serviced separately. The clutch PC solenoid 4 flows fluid to the 2-6 clutch when commanded ON and exhausts fluid when commanded OFF. The clutch PC solenoid 4 regulates the transmission fluid pressure to the 2-6 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 expected transmission gear ratio to the calculated gear ratio for each commanded gear.
Conditions for Running the DTC
P2714
* No ISS DTCs P0716 or P0717.
* No OSS DTCs P0722 or P0723.
* No IMS DTCs P1825 or P1915.
* The transmission input shaft speed is 60 RPM or greater.
* The transmission fluid temperature is 0°C (32°F) or greater.
* 2-6 clutch is commanded ON.
P2715
* No ISS DTCs P0716 or P0717.
* No OSS DTCs P0722 or P0723.
* No IMS DTCs P1825 or P1915.
* The transmission fluid temperature is 0°C (32°F) or greater.
* The transmission output shaft speed is 200 RPM or greater.
* 2-6 clutch is commanded OFF.
Conditions for Setting the DTC
P2714
The TCM detects an incorrect on-coming clutch gear ratio, or flare, when the 2-6 clutch is commanded ON for 2.25 seconds and the transmission input shaft speed is 100 RPM or greater from the anticipated input shaft speed.
P2715
The TCM detects an incorrect off-going clutch gear ratio, or tie-up, when the 2-6 clutch is commanded OFF for 1.2 seconds and the transmission input shaft speed is 40 RPM or less from the anticipated input shaft speed.
Action Taken When the DTC Sets
* DTCs P2714 and P2715 are Type A DTCs.
* The TCM commands maximum line pressure.
* The TCM inhibits TCC.
* The TCM freezes transmission adaptive functions.
* The TCM defaults the transmission to third gear if the current gear is 1st, 2nd, or 3rd; or fifth gear if the current gear is 4th, 5th, or 6th gear.
Conditions for Clearing the DIC/DTC
DTCs P2714 and P2715 are Type A DTCs.
Reference Information
Description and Operation
Transmission General Description Transmission General Description
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Programming and Relearning for scan tool information
Special Tools
* DT-47825 Control Solenoid Test Plate
* J 21867 Pressure Gauge
Circuit/System Verification
1. Perform the Transmission Fluid Level and Condition Check Transmission Fluid Level and Condition 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 Transmission Fluid Replacement.
2. Operate the vehicle in drive with the calculated throttle position greater than 15 percent to obtain 72 km/h (45 mph) and achieve 5th gear. Perform this maneuver 2 times. The DTCs should not set.
3. 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.
Circuit/System Testing
1. Ignition OFF, remove the line pressure test hole plug and install the J 21867 to the transmission.
2. Perform the Line Pressure Check Line Pressure Check. Verify the transmission line pressure gauge is within the range specified in the Line PC Solenoid Valve Pressure table. Refer to Solenoid Valve Pressure Solenoid Valve Pressure.
• If not within the specified range, repair as necessary. Refer to Fluid Pressure High or Low Fluid Pressure High or Low for further diagnosis.
3. Ignition OFF, remove the control solenoid (w/body and TCM) valve assembly.
4. Install the DT-47825 to the control solenoid (w/body and TCM) valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test for detailed instructions.
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. A pressure change should occur.
• If a pressure change does not occur, replace the control solenoid (w/body and TCM) valve assembly.
6. Inspect for the following conditions and repair/replace as necessary:
* Lower control valve body for a stuck valve, debris or damage
* 2-6 clutch assembly for damage
Repair Instructions
Important:
* Perform the Service Fast Learn Adapts 6T70/6T75 - Automatic Transmission following all transmission related repairs.
* Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection Control Solenoid Valve and Transmission Control Module Assembly Inspection.
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Control Valve Lower Body and Upper Body Replacement Control Valve Lower Body and Upper Body Replacement
* Low and Reverse Clutch and 1-2-3-4 Clutch Plate Removal 8. Low and Reverse Clutch and 1-2-3-4 Clutch Plate Removal
* Control Module References Programming and Relearning for control solenoid (w/body and TCM) valve assembly replacement, setup, and programming