Description And Operation
DESCRIPTION
| 1 - M6 Valve Body Bolt Hole |
| 2- M5 Valve Body to Solenoid Body Bolt Hole |
| 3 - Wiring Harness for Park Release Solenoid |
| 4 - Solenoid A |
| 5 - Solenoid D |
| 6 - Solenoid B |
| 7 - Solenoid E |
| 8 - Solenoid C |
| 9 - Torque Converter Clutch (TCC) Solenoid |
| 10 - Line Pressure Solenoid |
| 11 - Park Release Solenoid |
| 12 - High Impulse Solenoid (HIS) Wire Harness Connector |
| 13 - Output Shaft Speed (OSS) Sensor |
| 14 - Park Hold Solenoid |
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 solenoids are integrated into the Transmission Control Module Assembly (TCMA) of the 8HP transmission and are not replaceable individually.
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 based on the position of the accelerator pedal, shifter, and vehicle speed as determined by the PCM based on input from the Input Speed Sensor (ISS), Output Speed Sensor (OSS) and ABS module.
Solenoids
The EDS solenoid are of two colors to differentiate their characteristic curves:
There are two types of EDS solenoid for regulating the pressure:
- The yellow EDS have a rising characteristic curve; there is no control pressure when they are not powered.
- The blue EDS have a falling characteristic curve; the maximum control pressure is obtained when the solenoid valves are not powered.


