What Is a Mechatronic Unit?

The control centre of the gearbox is described as the mechatronic unit. It is found in the gearbox where we have the direct-shift gear oil (DSG). Its task is to manage the torque converter and the clutch pad of the gearbox via the transmission fluid under specific pressure. It is capable of performing shift operations in a second.

 The gearbox’s control unit is in constant communication with the engine control unit, and this helps determine the right time when changing gear.

 Simply put, the mechatronic unit is a computerised control part of the dual-clutch system. This unique advanced dual-clutch automatic transmission is found in many cars, but mostly Audis, Volkswagens and Porsches. The dual-clutch transmission consists of two sub gearboxes, each with its clutch, that work together to shift the gear.

 At Geartronix we specialize in the repair, replacement, and installation of mechatronics for Audi, VW and Porsches.

Common Problems of Mechatronic Units?

• Failing temperature sensor:

Many times, the failure starts with a failing temperature sensor, either completely or partially. If the data sent to the sensor is incorrect, the computer will do what it believes is correct based on the incorrect data. When this occurs, specific gears stop working, either sequentially or all at once.

• Valve body gaps:

Failure in the mechatronic unit can also occur because of an issue with the automatic transmission in general. The presence of elements that are not part of the transmission fluid’s composition can cause rapid wear and damage to the valve body, causing it to fail. The valve body gaps have the following:

• Springs
• Plates with fluid pad and
• Gasket with gaps in specific places
• Manual valves (on the upper plate) which determine whether the car is in parking, drive or neutral, or reverse position.
• Valve seat
• Hydraulic valves
• Plastic and metal balls

• Faulty solenoid:

More than one sensor can get faulty and getting the data from them will be impossible. Electronic components on the mainboard may get damaged, and errors can appear on the software program of the gear change control due to incorrect data. The most common defects occurring in the control units are; incorrect solenoid operation and periodic errors during diagnostic tests.

 These symptoms can be caused by faulty mechatronics

1. Gearbox keeps selecting the neutral position.
2. Inability to select gears.
3. Clonking in gears.
4. Selector warning lights.
5. “PRNDS” lights flashing.

How to troubleshoot a mechatronic unit?

Reading or obtaining trouble codes is important because it simplifies troubleshooting and lowers the cost of repairing a mechatronic unit. All mechatronics appear the same, but they have a variety of HW (hardware) and SW (software) versions. When a unit begins to fail, it can be difficult to locate an exact replacement.

If there is a fault in solenoid control, speed sensor, range sensor, or mainboard electronics, it must be inspected in a laboratory. After inspection, necessary repairs can be carried out on the areas affected. Sometimes, repairs are not possible, and you will need a new mechatronic unit or a reconditioned control unit.

The oil passages in the plates are visually inspected for residues or any foreign particles.  The corrector incorrect operation of the valve is known with the help of chats between the technician and the mechanic. Diagnosing and fixing a complex and sophisticated car part requires precision and specialized skills. The first is performed manually by a valve machine for each valve.

Why choose Geartronix?

1. Geartronix has more than 20 years of experience in electronics and gearbox rebuilding, Geartronix DSG Centre has the solution for all Porsche, Volkswagen DSG, and Audi S-Tronic gearboxes. All repairs are done in-house at our state-of-the-art facility by experienced, qualified technicians
2. Geartronix DSG Centre currently has 10 frame-engaging two-post lifts for the removal and refitting of gearboxes and mechatronic units.
3. The Geartronix workshop takes up an expansive 1500 SQ making it one of the biggest of its kind in South Africa.
4. There is also a dedicated lift used to carry out inspections and diagnosis, as well as a dedicated quality control lift for a final control inspection on all cars that have work carried out at Geartronix DSG Centre.