6L50/6L80/6L90 - 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 valve assembly, which has no serviceable parts. The PC solenoid 4 regulates transmission fluid pressure to the 2-6 clutch regulator valve which controls pressure to the 2-6 clutch. The TCM calculates gear ratio based on the RPM signals from the 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 other ECM or TCM DTCs are set.
* The accelerator pedal position is 0.5 percent or greater.
* The output speed is 16 RPM or greater.
* The ignition voltage is 8.6 volts or greater.
* The engine speed is 400 RPM or greater for 5 seconds.
* The transmission temperature is -6.6°C (20°F) or greater.
* The throttle position signal is valid.
* High side driver (HSD) is enabled.
* The PC solenoid 4 is commanded ON, applying the 2-6 clutch.
P2715
* No other ECM or TCM DTCs are set.
* The accelerator pedal position is 0.5 percent or greater.
* The output speed is 16 RPM or greater.
* The ignition voltage is 8.6 volts or greater.
* The engine speed is 400 RPM or greater for 5 seconds.
* The transmission temperature is -6.6°C (20°F) or greater.
* The throttle position signal is valid.
* High side driver (HSD) is enabled.
* The PC solenoid 4 is commanded OFF, releasing the 2-6 clutch.
Conditions for Setting the DTC
P2714
The TCM has detected an incorrect gear ratio or neutral condition when the 2-6 clutch is commanded ON. This condition must occur 3 times.
P2715
The TCM has detected an incorrect gear ratio change when the 2-6 clutch is commanded OFF during a shift or when 2nd gear ratio is detected in 1st gear. This condition must occur 3 times.
Action Taken When the DTC Sets
P2714
* DTC P2714 is a Type A DTC.
* The TCM commands maximum line pressure.
* The TCM inhibits Tow/Haul mode.
* The TCM freezes transmission adaptive functions.
* The TCM inhibits TAP Up/Down function.
* The TCM inhibits Manual Up/Down Shift with the shift selector.
* The TCM limits the transmission to Reverse gear and 3rd gear operation.
P2715
* DTC P2715 is a Type A DTC.
* The TCM commands maximum line pressure.
* The TCM inhibits Tow/Haul mode.
* The TCM freezes transmission adaptive functions.
* The TCM inhibits TAP Up/Down function.
* The TCM inhibits Manual Up/Down Shift with the shift selector.
* The TCM limits the transmission to 2nd gear operation.
Conditions for Clearing the DIC/DTC
DTCs P2714 and P2715 are Type A DTCs.
Diagnostic Aids
Before performing a road test, configure and setup the scan tool for snapshot mode. This will allow you to display, monitor, and verify multiple transmission data parameters at one time, after the road test.
Reference Information
Connector End View Reference
* Component Connector End Views (Connector End Views By Name)
* Inline Harness Connector End Views (Connector End Views By Number)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
Description and Operation
* Electronic Component Description (Electronic Component Description)
* Transmission General Description (Transmission General Description)
* Transmission Component and System Description (Transmission Component and System Description)
* Park - Engine Running (Park - Engine Running)
* Reverse (Reverse)
* Neutral - Engine Running (Neutral - Engine Running)
* Drive Range, First Gear Engine Braking (First Gear Engine Braking)
* Drive Range, First Gear (First Gear)
* Drive Range, Second Gear (Second Gear)
* Drive Range, Third Gear (Third Gear)
* Drive Range, Third Gear Default (Third Gear Default)
* Drive Range - Fourth Gear (Fourth Gear)
* Drive Range, Fifth Gear (Fifth Gear)
* Drive Range, Fifth Gear Default (Fifth Gear Default)
* Drive Range, Sixth Gear (Sixth Gear)
* Fluid Passages (Fluid Passages)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference
Control Module References (Control Module References)for scan tool information
Special Tools
* DT-47825 - Control Solenoid Test Plate
* DT-47825-10 - Jumper Harness
For equivalent regional tools, refer to Special Tools (6L45/6L50/6L80/6L90 - Automatic Transmission).
Circuit/System Verification
Note: If other DTCs are set, diagnose those DTCs first.
1. Engine idling in Park, with parking brake applied and drive wheels chocked.
2. Perform the Transmission Fluid Level and Condition Check (Transmission Fluid Level and Condition Check) to verify correct fluid level and condition.
3. Monitor the Transmission Fluid Pressure (TFP) switch 3 with a scan tool. Place the gear select lever in Park, Reverse, and Neutral range. Verify the TFP switch 3 parameter states are correct for Park, Reverse, and Neutral. Refer to Transmission Fluid Pressure Switch Logic (Transmission Fluid Pressure Switch Logic).
4. Place the gear select lever in Drive range. Command the shift transmission with a scan tool through all forward ranges. Verify the TFP switch 3 parameter states are correct for all forward ranges. Refer to Transmission Fluid Pressure Switch Logic (Transmission Fluid Pressure Switch Logic).
5. Engine idling in Park, verify with a scan tool the Transmission ISS/OSS supply voltage test status parameter displays OK.
6. Engine idling in Park. Observe the Transmission ISS parameter on the scan tool, while varying the engine speed. The Transmission ISS parameter should vary with engine speed and not drop out.
7. Operate the vehicle at 16-32 km/h (10-20 mph) while observing the Transmission OSS parameter on the scan tool. The Transmission OSS parameter should vary with the vehicle speed and not drop out.
Note: Perform a scan tool snapshot, during the road test.
8. Perform the Road Test (Road Test). Verify the transmission operation performs as indicated in the road test instructions.
9. Review the scan tool snapshot data. Verify the following transmission data parameters display the correct values for each gear range:
* Transmission ISS
* Transmission OSS
* PC Solenoid 4
* TFP Switch 3
10. Operate the vehicle within the Condition 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. Perform the Line Pressure Check (Line Pressure Check). Verify the transmission line pressures are within the specified ranges.
• If not within the specified ranges, refer to Fluid Pressure High or Low (Fluid Pressure High or Low).
2. Ignition OFF, remove the Q8 control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement (6L45/6L50/6L80/6L90 - Automatic Transmission).
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). Test all solenoids on the Q8 control solenoid valve assembly. A pressure change should occur for each solenoid valve.
• If the Q8 control solenoid valve assembly does not pass the performance test, replace the Q8 control solenoid valve assembly.
4. Listed in the chart below, are conditions for each component that could set DTC P2714 or P2715. Carefully inspect each component for that condition. Repair or replace as necessary.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Control solenoid valve assembly replacement. Refer to Control Module References (Control Module References) for replacement, setup, and programming.
* Perform the Service Fast Learn Adapts (6L45/6L50/6L80/6L90 - Automatic Transmission) following all transmission related repairs.