2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1682
1. Ignition OFF. Remove the control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly
Replacement (See: Powertrain Management/Transmission Control Systems/Actuators and Solenoids - Transmission and
Drivetrain/Actuators and Solenoids - A/T/Shift Solenoid/Service and Repair).
2. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (See: Transmission and Drivetrain/Automatic
Transmission/Transaxle/Testing and Inspection/Component Tests and General Diagnostics/6T70/6T75 - Automatic Transmission/Control
Solenoid Valve and Transmission Control Module Assembly Inspection).
3. Place the control solenoid valve assembly on a clean work surface near the transmission assembly.
4. Connect DT-47825-20 - jumper harness between the vehicle wire harness electrical connector, and the control solenoid valve assembly
electrical connector.
5. Ignition ON, verify with a scan tool that the TFP Switch 1, TFP Switch 3, TFP Switch 4, and TFP Switch 5 parameters changes states when
gently pushing on each TFP switch with the eraser end of a pencil.
瀚慖f any TFP Switch parameter does not change states, replace the control solenoid valve assembly.
Repair Instructions
Note:
* Perform the Service Fast Learn Adapts (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing and
Inspection/Programming and Relearning) following all transmission related repairs.
* Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (See: Transmission
and Drivetrain/Automatic Transmission/Transaxle/Testing and Inspection/Component Tests and General Diagnostics/6T70/6T75 - Automatic
Transmission/Control Solenoid Valve and Transmission Control Module Assembly Inspection).
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning) for control solenoid valve assembly replacement, setup, or
programming
P0877
DTC P0877 or P0878
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0877
- Transmission Fluid Pressure (TFP) Switch 4 Circuit Low Voltage
DTC P0878
- Transmission Fluid Pressure (TFP) Switch 4 Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The transmission fluid pressure (TFP) switch 4 is part of the control solenoid valve assembly which has no serviceable parts. The TCM supplies a
signal circuit to the TFP switch 4. The TFP switch 4 has an internal case ground. TFP switch 4 is normally closed or LOW. When oil pressure is
present at the TFP switch 4, the switch is open or HIGH. The normally LOW pressure control solenoid 5 controls pressure to the 1-2-3-4 clutch
regulator valve. The TCM monitors the TFP switch 4 to determine the position of the 1-2-3-4 clutch regulator valve. When the 1-2-3-4 clutch is
commanded OFF, pressure is present on the TFP switch 4. When the 1-2-3-4 clutch is commanded ON, the 1-2-3-4 clutch regulator valve moves
and pressure to the TFP switch 4 is exhausted through the 1-2-3-4 clutch regulator valve.
Conditions for Running the DTC
