Automotive markets around the world are interconnected on many levels, particularly in terms of powertrains. As ATRA is an international organization, we monitor developments in the transmission industry worldwide. As a result, a particular transmission consistently tops the charts as being most likely to require repair in the near future, and that would be the DQ200. From Europe to Australia and beyond, these units are entering shops at a steady pace.
Manufactured by Škoda Auto, the DQ200 began production in 2007 and remains in production to this day. It is also known as the 0AM, 0CW, DSG7, and a few other, less popular names. There were more than four million units produced, and it doesn’t appear that they will disappear…ever! Several updates to the unit and software controls address known problematic areas. However, this transmission will inevitably raise concerns over time. Let’s take a closer look at this unit.
UNIT OVERVIEW
This unit is a direct replacement for the DQ250 (six-speed) wet dual-clutch transmission. The DQ200 is an automatically shifted, seven-speed, dual dry clutch unit that utilizes hydraulic controls to operate the shifting and clutch actuators. 
The control assembly is referred to as a mechatronic system and features a separate sump (and oil pump) to operate the actuators and solenoids. The gearbox, like other DSG units, is two manual transmissions in a single case. There are two input shafts and two outputs, with an odd and even gearset contained within a common sump. The dual dry clutch assembly is mated to the engine through a dual mass flywheel. When everything works as designed, the transmission shifts wonderfully. However, repeated starts from a stop will yield some not-so-smooth launches, which is typical for any dry clutch unit.
VEHICLE APPLICATIONS
The DQ200 is found in several makes and models, most of which are not found in the US (Figure 1). The most popular North American application is the Volkswagen Jetta Hybrid. Other markets have the Volkswagen Golf and Skoda vehicles as their forerunners. The transmission is found behind smaller displacement gasoline (petrol) and diesel applications, ranging from 1.2L to 2.5L.
PRECAUTIONS
Always use the OEM-recommended fluids when servicing this unit. The DQ200 has two sumps: one for the transmission gearbox and one for the Mechatronic assembly. Each sump is filled by capacity only (Figure 2).
The mechatronic assembly uses a mineral-based type of oil. If there are any leaks, the assembly should be emptied, resealed, and filled. The gearbox uses a fluid that resembles GM Synchromesh. The synchronizers inside the unit are molybdenum-coated brass rings, which require a lower viscosity fluid than gear lube to function correctly.
Another area to address cautiously is the Mechatronic unit. Inside is an accumulator used to maintain a volume of pressurized oil, ready to operate actuators and solenoids for shifting and clutch actuation (Figure 3). The accumulator is charged with an inert gas that acts on a piston on one side, while oil is pumped into the other side. The oil pressure inside the accumulator is typically between 40 bar (580 psi) and 60 bar (870 psi), but can rise as high as 70 bar (1,015 psi). A blow-resistant cover protects it. 
However, the cover must be removed to service the Mechatronic components. Always use extreme caution when removing the cover. Always treat the assembly as if the accumulator failed until you verify otherwise. The force of the accumulator’s discharge can severely injure or kill you.
THE PROBLEMS
Several drivability and functional issues are addressed with this transmission by updating the TCM programming. Always search for the latest OEM programming to ensure your module is up to date.
Powertrain-related issues can occur either within or outside the transmission. The DQ200 has its share of both. Therefore, it is beneficial to have a working knowledge of all the components that could cause a customer to bring their vehicle into your shop with issues to be addressed. Some of these issues include the following:
- No movement
- No Reverse, Forward is good
- Clutch shudder, slipping, and vibrations
- Rattling noises
When the shift indicator (PRNDS) in the dash blinks, it indicates that a fault in the TCM and/or a failure management mode has been initialized. A blinking shift indicator may be accompanied by clutch shudder or vibration, no movement, or the unit being locked into one gear only. Intermittent faults typically indicate that a more significant problem is lurking on the horizon. Unfortunately, just pulling trouble codes and following the diagnostic path doesn’t always lead you to the root cause of the problem. You should be aware that this unit has a pattern of failures that occur quite frequently.
THE VALVE BODY CASTING
The most common failure in the DQ200 unit is the casting failure at the accumulator (Figure 4). It is an area that is under extremely high pressure and made of aluminum. With time, the housing cracks and begins to leak. 
No drivability symptoms may be noticed at first. So, catching a failure in progress requires monitoring scan data from the TCM. Simply monitoring the Mechatronic pressure switch data while the vehicle is idling at operating temperature can reveal an issue. If the pressure drops to 40 bar with no components functioning, you must address an internal leak. Note that shift and clutch actuators may leak, but they will not cause a pressure drop while idling (with the clutches open) in neutral or park.
There are options for repairing the mechatronic system without replacing the entire assembly. The casting is available from numerous aftermarket sources, allowing factory-level repair. However, aftermarket companies produce a modified accumulator assembly that works with the damaged valve body casting, creating an extremely reliable repair. Contact your soft parts supplier for available repair options.
THE TCM
The TCM on this unit is located on the valve body and is part of the Mechatronic assembly. It relies on oil inside the Mechatronic assembly for cooling. The earliest versions of the DQ200 utilized a corrosive hydraulic oil that reacted with the TCM circuit board, causing premature failure. The OEM-recommended oil has been updated to address the problem.
Even with updates, the TCM has a relatively high failure rate. Overheating is a major issue that causes it to fail. The source of overheating is not clear until you examine what is happening inside this unit more closely.
The cracking valve body issue that we mentioned earlier causes the Mechatronic electric pump to work harder to meet pressure and volume demands. The electric pump motor often remains on for much longer than intended under normal conditions, eventually causing the feed circuit on the TCM to overheat and burn. A customer may operate their vehicle for an extended period with intermittent issues, which leads to the pump motor circuit being energized beyond the capacity of the TCM design.
Other areas of concern exist in the circuit board and connector construction. Solder joints on the TCM board frequently fail. The CAN BUS and electric pump feed circuits are the most common failure points. If you’re skilled at soldering, this could be an easy fix. Otherwise, you would need to replace the TCM. The TCM connector and vehicle harness plug must be verified and repaired as needed.
CLUTCH DURABILITY
These units are paired with small petrol (gas) and diesel engines that can last a long time with proper maintenance. The clutch assembly has an average lifespan of 80,000 kilometers. Vehicles driven in the city or for severe duty use may experience a shorter life. Unlike conventional single-disc clutch transmissions, the dual-clutch assembly replacement is rather expensive (around $1,000 US plus labor and extras). Of course, the price tag tends to give owners pause about fixing the vehicle. Always price out the parts needed to provide the customer with a realistic estimate.
When the vehicle clutch assembly is set up correctly, it will perform as new. Removing, installing, and setting up the clutch requires special tools. Shims are used to adjust the freeplay of the clutches within the published specifications. A quality toolkit will include the setup procedure. Contact your soft parts supplier to purchase a service kit.
6TH/REVERSE CLUTCH FORK FAILURE
A sudden complaint of no reverse is common with these units. Everything can work great until that one time it just doesn’t back up. Sometimes, it can be intermittent, but most of the time, reverse will not return, and a code indicating a sensor G490-related fault may be present. A test drive of the vehicle will also show that there is no 6th gear either.
The no reverse or sixth gear problem is attributed to the 6th/Reverse shift fork failing. The area of concern lies in the shift rail bearing guides (Figure 5). The plastic retainers for the shift rail bearings become brittle and break, causing the shift rail to travel out of line when operated. Often, the shift rail will jam due to debris from the plastic retainer and the side load placed on the shift fork as it attempts to move the selector sleeve. There is an aftermarket repair; however, extracting the debris from the failed retainer can be a challenging task.
RATTLING NOISES, DUAL MASS FLYWHEEL ISSUES
Rattling noises while starting the vehicle may indicate an issue outside the transmission. The DQ200 features a dual-mass flywheel. When the assembly is working correctly, it offers smooth, seamless operation by absorbing normal engine vibrations caused by cylinder firing. Over time, the springs used to absorb vibrations begin to wear, allowing clearance between the suspended and anchored masses of the flywheel. 
The clearance allows the springs to rattle when they are unloaded between engine firing strokes. The rattling noise is most noticeable during engine cranking and most pronounced with diesel applications. In extreme cases, the springs can wear through to the engine side, causing a no-crank condition (Figure 6) and possibly damaging the engine block. Always inspect the flywheel when servicing the clutch assembly or removing the transmission.
FAILSAFE CONDITIONS
It is essential to be aware of some failsafe operating strategies that are used to protect the transmission. Failsafe operation can be mistaken for a faulty unit. In most cases, the TCM commands the clutches to open (neutral) whenever transmission sensor data is conflicting or missing. Listed here are a few conditions for a TCM commanded failsafe no move:
- Conflicting or missing shift rail position data
- Mechatronic temperature is too high
- Clutch temperature (calculated) is too high
- Mechatronic pressure is too low (below 40 bar)
There are other conditions that can cause no-move or limited range operation that are usually accompanied with DTCs. Scanning for all codes in all modules is necessary to ensure that sensor data from other modules that affect TCM control is addressed.
When a transmission has been in the ‘real world’ for a considerable amount of time, it reveals areas of weakness and concern that must be addressed to return it to its full operational state. Often, aftermarket products help ensure that our repairs will stand the test of time. However, some components only allow us to deliver up to the OEM standard. Knowing our options helps us to deliver the goods to our customers with a warranty and promise that we can confidently stand behind.
