Driving a Mercedes-Benz has an irresistible appeal to everyone. These sturdy vehicles are well designed, and their dynamics are outstanding. It’s a known brand for its impressive power, longevity, durability, and sophistication. However, despite being the most reliable brand in the market, sometimes Mercedes vehicles experience transmission issues.
According to survey and research, Mercedes-Benz experiences a lot of wear and tear in its transmission, and this is due to constant use and its complexity. The most common problems with the transmission in Mercedes-Benz involve hard shifting, and in some cases, no shifting. It is advisable to have a complete diagnostic run of your Mercedes Benz when dealing with gear selector issues to determine the exact problem.
The majority of the gear selector issues witnessed in Mercedes-Benz are due to inappropriate transmission oil levels, oil slippage, failure of the primary pump, faulty valve bodies, or water. The transmission system in these particular scenarios can go into the “limp mode”, crippling the transmission shift gears and causing it to default to a suitable gear- usually second or third gear. This happens to protect the transmission system from further damage. However, a faulty control unit in the transmission is the primary cause of failure in the gearbox.
How to Handle a Malfunctioning Gearbox
The state of limp mode in the transmission indicates a malfunction in shifting gears. Since the system of transmission of the gears is complicated, it requires an experienced Mercedes professional in carrying out the diagnostic, using computerized equipment that can read the codes in the transmission system.
The codes from this equipment will indicate the cause to the malfunctioned gearbox and whether there is a mechanical or electronic failure. If the diagnosis indicates a failure in the electronic components, then the main problem could be faulty solenoids, speed sensors, selector sensors, or even the transmission module itself. Usually, the modules are damaged when there is voltage overload, vibrations, water, and thermal stress.
The module is an essential component in controlled transmission, and when damaged, it requires replacing or repairing to get the car on the road. The dealers, for instance, may supply the control module with a complete valve body, which will incur extra costs. However, in many cases, the valve body is not the cause of transmission failure and thus requires replacing the control unit of the transmission only.
At Auto Europa, based in San Francisco, CA, we provide new and reconditioned transmission modules, and can recode the modules when necessary.
The first step in troubleshooting the transmission of a Mercedes-Benz is to check the level of the fluid. The fluid level should not be too low, and this is common especially if the car is more than 8 years old. The fluid level can be low due to seepage, and the vehicle will set into limp mode immediately when it detects low fluid level.
Another way of troubleshooting is reading and clearing the faulty control codes. A Mercedes Benz typically stores its fault codes when it goes into limp mode. The transmission codes are stored in the Transmission Control Unit. They can be retrieved and cleared with the help of an OBD scanner.
A Mercedes-Benz car could also set itself in limp mode when the battery is low. In this case, the battery should be replaced, and the OBD scanner can be used to delete faulty codes. A problem in communication with the valve body may lead to gear selector issues. In this case, a new valve body should be installed or replace the 13-pin connector plug O-ring. If the O-ring transmission plug is replaced, the OBD scanner will be required to remove the fault codes.
Trust the Professionals
Mercedes-Benz owners should not panic once the car goes into limp mode — this is an indicator that something is likely wrong with your gear selector, but that can be remedied. The transmission system of Mercedes-Benz is very reliable and durable, and our professionals at Auto Europa are prepared to help you with your transmission problems.
At Auto Europa, we have extensive experience with European automobiles, so we are thoroughly equipped to handle gear selector repairs in your Mercedes Benz. Call for an appointment or bring your car by today to speak with our expert service technicians.