There is no doubt that DSG gearboxes come with a number of benefits and deliver impressive performance and efficiency, however, the complexity of the design means there are potential weaknesses. Here are some common problems associated with DSG gearboxes:
- Faulty solenoid valves
- High pressure valve leaks
- Failures of electric motors
- Failure of high pressure pumps
- Sensor or other module failures
These issues could lead to you experiencing rough shifting, gear slippage, difficulty accelerating, your vehicle unexpectedly shifting into neutral, warning lights appearing, and some other indicators. Early detection of these problems is important if you are keen to prevent the damage escalating and leading to more expensive repairs.
What is a DSG Gearbox?
A DSG, or Direct Shift Gearbox, is a type of automatic transmission designed to provide you with the convenience of an automatic transmission while delivering the fuel efficiency and performance of a manual one. Unlike traditional automatics that make use of a torque converter, a DSG gearbox has two clutches. Think of it as two separate gearboxes working together.
One clutch handles even gears, while the other handles odd gears. This allows the DSG to pre-select the next gear so transmission shifts are almost instant. When it’s time to shift, the DSG simply disengages one clutch and engages the other, meaning your gear changes are not only extremely fast but also very smooth.
This leads to a much more responsive driving experience with little or no power loss in between gear changes. DSG gearboxes are regularly praised for their fuel efficiency in comparison with standard automatics. However, the complex design of the DSG gearbox can sometimes result in potential issues arising in the future.
Solenoid Valve Failure: What is it and How Do You Know its Happening
A solenoid valve is a tiny but highly effective switch located in a DSG gearbox. Its function is to control the flow of fluid and direct it to engage individual gears. When this valve fails it can make smooth gear changes difficult. Some of the main reasons solenoid valves fail include normal wear and tear, fluid contamination, electric faults, or problems with the transmission control module. If solenoid valves get stuck either open or closed, changing gear can become problematic. Problems with the solenoid valve are one of the most common problems faced by owners of cars with DSG gearboxes and the telltale signs include:
- Rough, jerky gear changes
- Your car continually slips in and out of gear
- Your gears only being late in engaging or not engaging at all
- The car getting stuck in one gear
- Trouble accelerating as normal
- Warning lights on the dash highlighting issues with your transmission
- Error codes that are related to solenoid performance showing up
Solenoid issues generally arise gradually but can quickly become apparent. If you notice any of these issues, contact the experts here at Auto Gearbox and we will assist you.
High Pressure Valve Leaks
DSG transmissions function at very high hydraulic pressures, which in some cases can be up to 1500 PSI. To generate this amount of pressure a high-pressure pump is used and managed by a set of valves.
With the passage of time and as a result of regular usage and fluid contamination, leaks can occur in the high-pressure control valves. This causes a loss of line pressure throughout the system, which stops you changing gear smoothly.
High-pressure leaks are a prevalent issue in DSG gearboxes the signs of which are the same as those found with solenoid issues. Again while leaks may initially be minor, they can escalate quickly making quick action essential if you want to avoid more extensive damage.
Electric Motor Failure
A dedicated electric motor drives the high-pressure hydraulic pump within DSG transmissions. The way this is set up means that the pump has the ability to function independently of engine speed, keeping the pressure at a steady level at all times.
However, over time, the electric motor may experience failures caused by things like worn bearings, wiring faults, or problems with the transmission control module. When the electric pump motor fails you will experience a total loss of hydraulic pressure, meaning that you will not be able to change gears using the DSG gearbox.
Telltale signs of a malfunctioning DSG gearbox are:
- There is no drive in forward or reverse gears
- Transmission will not shift at all
- Gear selector may flash or blink in PRNDS
- Loud whining noise from transmission
- Check engine light and transmission fault codes
When the electric motor fails it will result in an immediate lack of drive. If you are already moving your vehicle may roll a little way but you won’t be able to accelerate. When this happens you will need to repair the motor or replace the pump assembly.
High Pressure Pump Failure
As we mentioned earlier, DSG transmissions are reliant on an electric high-pressure pump for generating hydraulic pressure. Apart from the electric motor failure, the pump itself can also encounter issues.
Problems such as worn pump vanes, contamination making its way through the pump, or damage to any of the internal components, all play a part in pump failure. This in turn, will lead to a total loss of line pressure. If it doesn’t have enough pressure, the DSG clutches will fail to engage, rendering the gearbox unable to shift gears.
The signs of a malfunctioning DSG high-pressure pump are very similar to those of a faulty electric motor:
- No drive in any gear
- Transmission will not shift
- Gear selector flashing
- Loud noises from transmission
- Warning lights and error codes
You will need a professional to perform diagnostics to find out whether your problem is a broken electric motor or high pressure pump. Either way the offending part will need to be repaired or replaced. By identifying the problem early you can prevent other internal components becoming damaged.
DSG transmissions featured in Volkswagen, Audi, and other vehicles deliver impressive performance and efficiency. Yet, their intricate design may result in problems as they rack up mileage.
Common issues with DSG Gearboxes encompass failed solenoids, high-pressure leaks, electric motor or pump malfunctions, and electrical faults. Symptoms vary from rough shifting to complete transmission failure.
Should you detect any indications of trouble with your DSG transmission, get in touch with our team and we will provide the assistance that you need. Early detection is crucial in preventing costly repairs in the future.