GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P2723:  Clutch Pressure Control (PC) Solenoid 5 - Stuck Off

DTC P2724:  Clutch Pressure Control (PC) Solenoid 5 - Stuck On

Circuit/System Description

The clutch pressure control (PC) solenoid 5 is part of the control solenoid (w/body and TCM) valve assembly and is not serviced separately. The clutch PC solenoid 5 flows fluid to the 1-2-3-4 clutch when commanded ON and exhausts fluid when commanded OFF. The clutch PC solenoid 5 regulates the transmission fluid pressure to the 1-2-3-4 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

    • No DTCs P0716 or P0717.
    • No DTCs P0722 or P0723.
    • No DTCs P1825 or P1915.

P2723

    • The transmission input shaft speed is greater than 60 RPM.
    • 1-2-3-4 clutch is commanded ON.

P2724

    • The transmission output shaft speed is greater than 200 RPM.
    • 1-2-3-4 clutch is commanded OFF.

Conditions for Setting the DTC

P2723

The TCM detects an incorrect on-coming clutch gear ratio, or flare, when the 1-2-3-4 clutch is commanded ON for 0.5 seconds and either fail case below is achieved:

Fail Case 1

    • Output shaft speed is greater than 60 RPM.
    • The transmission input shaft speed is greater than 75 RPM from the anticipated input shaft speed.

Fail Case 2

    • Output shaft speed is less than 60 RPM.
    • The transmission input shaft speed is greater than 75 RPM from the anticipated input shaft speed.

P2724

The TCM detects an incorrect off-going clutch gear ratio, or tie-up, when the 1-2-3-4 clutch is commanded OFF for 0.5 seconds and the following is achieved:

    • The 1-2-3-4 clutch commanded pressure is 0 kPa for a calculated amount of time.
    • The transmission input shaft speed is less than 40 RPM from the anticipated input shaft speed.
    • The output shaft speed is greater than 60 RPM.

Action Taken When the DTC Sets

    • DTCs P2723 and P2724 are Type A DTCs.
    • The TCM freezes transmission adaptive functions.
    • DTC P2723 defaults to Reverse, Park, Neutral, 5th, or 6th gear.
    • DTC P2724 defaults to Reverse, Park, Neutral, 1st, or 2nd gear.

Conditions for Clearing the DIC/DTC

DTCs P2723 and P2724 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

Connector End View Reference

    •  Automatic Transmission Inline 16-Way Connector End View
    •  Automatic Transmission Internal Connector End Views
    •  Automatic Transmission Related Connector End Views

DTC Type Reference

    •  Diagnostic Trouble Code (DTC) Type Definitions
    •  Diagnostic Trouble Code (DTC) List/Type

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

    •  Scan Tool Output Controls
    •  Scan Tool Data List
    •  Scan Tool Data Definitions

Special Tools Required

    • DT-47825 Control Solenoid Test Plate
    • DT-47825-10 Jumper Harness

Circuit/System Verification

  1. Perform the Transmission Fluid Check .
  2. Turn ON the ignition, with the engine OFF.
  3. Important: 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. 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.
  7. If the DTC resets, go to Circuit/System Testing.

Circuit/System Testing

  1. Perform the Line Pressure Check .
  2. If the pressure is out of specification, correct this concern first.
  3. Perform the Control Solenoid Valve and Transmission Control Module Assembly Cleaning and retest the DTC as outlined in the Circuit/System Verification steps.
  4. If the DTC resets, continue on with testing.
  5. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection .
  6. If a concern is found, repair or replace the control solenoid (w/body and TCM) valve assembly.
  7. Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test .
  8. If the solenoid is found to be leaking or stuck closed, replace the control solenoid (w/body and TCM) valve assembly.
  9. Inspect the control valve upper body assembly for sticking valves, damage, scored bores, or debris.
  10. If a concern if found in the valve body, repair or replace the valve body as necessary.
  11. Inspect the 1-2-3-4 clutch assembly for damage.
  12. If a concern is found in the 1-2-3-4 clutch assembly, repair or replace as necessary.

Component Testing

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

PC Sol 5 Operation

Operating Conditions

Normal Operation

Stuck OFF

Stuck ON

Steady State Gears 1, 2, 3, 4

1, 2, 3, 4

Neutral

1, 2, 3, 4

Steady State Gears 5, 6

5, 6

5, 6

1, 2, 3, 4

Garage Shift

Park/Neutral/Reverse to Drive

Neutral

Drive Gear

Downshift from gears 5, 6 to 1, 2, 3, 4

1, 2, 3, 4

Neutral

1, 2, 3, 4

Upshift from gears 1, 2, 3, 4 to 5, 6

5, 6

5, 6

1, 2, 3, 4

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    • Control valve body replacement - refer to Control Valve Lower Body and Upper Body Replacement .
    • Control solenoid (w/body and TCM) valve assembly replacement - refer to Control Module References for replacement, setup, and programming.
    • 1-2-3-4 clutch assembly repair or replace - refer to 1-2-3-4 and 3-5 Reverse Clutch Overhaul .
    • Perform the Service Fast Learn Adapts .