* Shifting: The TCM determines when to shift gears based on various inputs, such as engine speed (RPM), vehicle speed, throttle position, and transmission fluid temperature. It aims for optimal fuel economy and performance.
* Torque Converter Lockup: It controls the torque converter clutch, engaging it at appropriate speeds to improve fuel efficiency and reduce slippage.
* Transmission Fluid Temperature Control: The TCM monitors transmission fluid temperature and adjusts shift patterns to prevent overheating.
* Solenoid Control: It manages the operation of various solenoids within the transmission that control hydraulic pressure to actuate the clutches and bands for shifting.
* Diagnostic Trouble Codes (DTCs): The TCM monitors its own operation and the transmission's performance. If it detects a problem, it will store a DTC, which can be read with a scan tool to diagnose faults.
* Communication with other Modules: The TCM often communicates with the Powertrain Control Module (PCM) – the engine's computer – to coordinate engine and transmission operation for smooth and efficient performance.
In short, the TCM ensures the automatic transmission operates correctly and efficiently under various driving conditions. A malfunctioning TCM can lead to problems ranging from rough shifting to complete transmission failure.
