Transmission control unit (TCU)
Location:
*Under the hood, at the rear of the engine
* Typically mounted on the left side of the engine compartment
Functions:
* Controls the operation of the automatic transmission (AT), including gear shifting, torque converter lock-up and gear ratio control.
* Receives signals from sensors such as speed sensor, throttle position sensor and gear position sensor.
* Optimizes gear shifting for a smooth and efficient driving experience.
* Protects automatic transmission from overloads, overheating and other potential problems.
Possible faults:
* Delay or jerking when shifting gears
* Gear slippage
* Switch to emergency mode (limitation of automatic transmission functions)
* Check Engine or other warning signals on the dashboard
Diagnostics and repair:
* Diagnosis of faults in the automatic transmission control unit is usually carried out using a fault code scanner.
* It may be necessary to replace the automatic transmission control unit if it is faulty or damaged.
* It is recommended that repairs be performed by a qualified transmission technician.