Functional Description - Valve Body Solenoids
DESCRIPTION:
The solenoids are integrated into the Transmission Control Module Assembly (TCMA) of the 8P75PH transmission. The solenoids are not serviced or replaced individually.
| 1 - M6 Valve Body Bolt Hole | 8 - Solenoid C |
| 2 - M5 Valve Body to Solenoid Body Bolt Hole | 9 - K0 Clutch (Separation Clutch) Solenoid |
| 3 - Wiring Harness for Park Release Solenoid | 10 - Line Pressure Solenoid |
| 4 - Solenoid A | 11 - Park Release Solenoid |
| 5 - Solenoid B | 12 - Integrated Electric Pump (IEP) Local Area Network (LIN) Wire Harness Connector |
| 6 - Solenoid D | 13 - Output Shaft Speed (OSS) Sensor |
| 7 - Solenoid E | 14 - Park Hold Solenoid |
GENERAL OPERATION:
The Transmission Control Module (TCM), or Transmission Control Module Assembly (TCMA) is extremely sensitive to Electrostatic Discharge (ESD). Always use a ground strap and follow the ESD guidelines in ELECTROSTATIC DISCHARGE (ESD) SENSITIVE DEVICES. Failure to follow these instructions may result in damage to the TCM/TCMA.
The TCM will actuate the valves via solenoids based on the position of the shifter, transmission fluid temperature, engine operating conditions, traction conditions, and driver demands. During a shift, the TCM will actuate the solenoids to match the gear ranges to the optimal torque range of the engine. This is based on input signals from the accelerator pedal, shifter position, Input Speed Sensor (ISS), Output Speed Sensor (OSS) and vehicle speed as determined by the Powertrain Control Module (PCM) and Anti-lock Brake System (ABS) module.
SOLENOID FUNCTIONALITY: There are two types of transmission solenoids designed for regulating pressure. The transmission solenoids are identified by two distinct colors to help differentiate their characteristics and function:
- Blue/Green transmission solenoids - These transmission solenoids have a falling characteristic curve (the maximum control pressure is obtained when the solenoid valves are not powered).
- White/Orange transmission solenoids - These transmission solenoids have a rising characteristic curve (there is no control pressure when they are not powered).