DQ400E DSG parts
The DQ400E is a 6-speed dual-clutch transmission with a wet clutch, designed for hybrid applications and also known as the 0DD. It combines the DSG principle with an interface to the vehicle’s hybrid system.
This page covers the symptoms most commonly associated with DQ400E faults, the mechatronic issues behind them, the fault codes that accompany them, and how to identify the correct mechatronic assembly or part.
Why DQ400E parts are family-specific
The DQ400E uses a wet dual clutch and is built for hybrid drivetrains, where the transmission works alongside an electric motor. The clutch and hydraulic design reflect that combined duty.
Faults on this family can involve hydraulic control and the hybrid control interface, because the transmission interacts with the hybrid system as well as the engine.
The mechatronic assembly holds the hydraulic and electronic control for the transmission. Because of the hybrid interface, confirming the exact unit and generation matters before ordering.
| Transmission family | DQ400E (6-speed hybrid DSG) |
|---|---|
| Also known as | 0DD |
| Clutch type | Wet dual clutch (hybrid) |
| Gears | 6 forward |
| Factory code | 0DD |
DQ400E parts we supply
Parts are listed per family because the hydraulic design, the clutch type and the electronics differ between DSG families. A part that fits one family will not necessarily fit another.
Sensors
Speed and position sensors used by the control unit to monitor the transmission.
Solenoids and valves
The electrically operated valves that direct hydraulic pressure inside the mechatronic unit.
Valve body components
Internal hydraulic components for the mechatronic assembly where a part-level repair is appropriate.
Service components
Filters, seals and service items relevant to the family.
When a part and when a mechatronic assembly
The right choice depends on the fault. We confirm it from the codes, the symptoms and the part number before quoting.
- Part-level repair. When a single sensor, solenoid or service component is at fault, a part-level replacement can be appropriate.
- Assembly-level replacement. When the fault involves the hydraulic control or the electronics as a whole, a replacement mechatronic assembly is usually the practical option.
- Confirmation before ordering. Send the fault codes and the part number and we will confirm which approach applies to your vehicle.
DQ400E fault codes and repair information
The fault codes and repair pages for this family help confirm which part is required before you order.
| Code | Description | Category | Status |
|---|---|---|---|
| 30097 | Transmission fluid pressure sensor — manufacturer event-memory code | Pressure sensor | Review |
DescriptionThe DQ400E transmission control unit stores 30097 when it detects the following condition: Transmission fluid pressure sensor — manufacturer event-memory code. The fault concerns a pressure sensor or pressure switch in the transmission. The control unit uses these signals for clutch and system pressure control, and stores the code when the signal is out of range, too low or implausible. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P0218 | Transmission overtemperature condition | Hydraulic pressure | Review |
DescriptionThe DQ400E transmission control unit stores P0218 when it detects the following condition: Transmission overtemperature condition. The fault concerns the hydraulic supply of the mechatronic unit. The control unit compares the required system pressure with the measured pressure and stores the code when the pressure is too low, too high, builds up too slowly, or the pump runs outside its normal operating time. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P0607 | Control module — implausible operation / hardware related | Internal control unit (TCU) | Review |
DescriptionThe DQ400E transmission control unit stores P0607 when it detects the following condition: Control module — implausible operation / hardware related. The fault originates in the transmission control electronics integrated into the mechatronic unit. The unit's self-diagnosis has detected an internal error, an implausible internal value or a software problem. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P0715 | Input / turbine speed sensor A — circuit | Speed sensor | Review |
DescriptionThe DQ400E transmission control unit stores P0715 when it detects the following condition: Input / turbine speed sensor A — circuit. The fault concerns a speed signal. The control unit needs the input (clutch/turbine) and output shaft speeds to control shifts and clutch slip, and stores the code when a signal is missing, implausible or electrically faulty. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P0731 | Gear 1 — incorrect ratio | Gear ratio / gear loss | Review |
DescriptionThe DQ400E transmission control unit stores P0731 when it detects the following condition: Gear 1 — incorrect ratio. This is a mechanical plausibility check: the control unit compares the input and output shaft speeds with the ratio expected for the selected gear. The code is stored when the calculated ratio does not match or a gear drops out unexpectedly. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P074A | Gear 1 — incorrect ratio | Gear ratio / gear loss | Review |
DescriptionThe DQ400E transmission control unit stores P074A when it detects the following condition: Gear 1 — incorrect ratio. This is a mechanical plausibility check: the control unit compares the input and output shaft speeds with the ratio expected for the selected gear. The code is stored when the calculated ratio does not match or a gear drops out unexpectedly. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P0842 | Transmission fluid pressure sensor — low signal | Pressure sensor | Review |
DescriptionThe DQ400E transmission control unit stores P0842 when it detects the following condition: Transmission fluid pressure sensor — low signal. The fault concerns a pressure sensor or pressure switch in the transmission. The control unit uses these signals for clutch and system pressure control, and stores the code when the signal is out of range, too low or implausible. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P0867 | Transmission fluid pressure — low / implausible | Hydraulic pressure | Review |
DescriptionThe DQ400E transmission control unit stores P0867 when it detects the following condition: Transmission fluid pressure — low / implausible. The fault concerns the hydraulic supply of the mechatronic unit. The control unit compares the required system pressure with the measured pressure and stores the code when the pressure is too low, too high, builds up too slowly, or the pump runs outside its normal operating time. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P0962 | Pressure control valve 1 — low control current | Valve / solenoid electrical | Review |
DescriptionThe DQ400E transmission control unit stores P0962 when it detects the following condition: Pressure control valve 1 — low control current. The fault is electrical: the control unit monitors the current and resistance of each solenoid and pressure control valve, and stores the code when it detects an open circuit, a short circuit or a control current outside the expected range. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P0966 | Pressure control valve 2 — low control current | Valve / solenoid electrical | Review |
DescriptionThe DQ400E transmission control unit stores P0966 when it detects the following condition: Pressure control valve 2 — low control current. The fault is electrical: the control unit monitors the current and resistance of each solenoid and pressure control valve, and stores the code when it detects an open circuit, a short circuit or a control current outside the expected range. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P172A | Hydraulic pressure — too high | Hydraulic pressure | Review |
DescriptionThe DQ400E transmission control unit stores P172A when it detects the following condition: Hydraulic pressure — too high. The fault concerns the hydraulic supply of the mechatronic unit. The control unit compares the required system pressure with the measured pressure and stores the code when the pressure is too low, too high, builds up too slowly, or the pump runs outside its normal operating time. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P172B | Hydraulic pressure — too low | Hydraulic pressure | Review |
DescriptionThe DQ400E transmission control unit stores P172B when it detects the following condition: Hydraulic pressure — too low. The fault concerns the hydraulic supply of the mechatronic unit. The control unit compares the required system pressure with the measured pressure and stores the code when the pressure is too low, too high, builds up too slowly, or the pump runs outside its normal operating time. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P1735 | Clutch 1 position sensor — electrical fault | Clutch faults | Review |
DescriptionThe DQ400E transmission control unit stores P1735 when it detects the following condition: Clutch 1 position sensor — electrical fault. The fault concerns clutch control: engagement, adaptation, torque limitation or clutch temperature. The control unit compares the commanded clutch position or pressure with the measured value and stores the code when the difference or the adapted value leaves the permitted range. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P1736 | Clutch 2 position sensor — electrical fault | Clutch faults | Review |
DescriptionThe DQ400E transmission control unit stores P1736 when it detects the following condition: Clutch 2 position sensor — electrical fault. The fault concerns clutch control: engagement, adaptation, torque limitation or clutch temperature. The control unit compares the commanded clutch position or pressure with the measured value and stores the code when the difference or the adapted value leaves the permitted range. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P179C | Main pressure valve — electrical malfunction | Valve / solenoid electrical | Review |
DescriptionThe DQ400E transmission control unit stores P179C when it detects the following condition: Main pressure valve — electrical malfunction. The fault is electrical: the control unit monitors the current and resistance of each solenoid and pressure control valve, and stores the code when it detects an open circuit, a short circuit or a control current outside the expected range. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P17BF | Hydraulic pump system overload protection | Hydraulic pressure | Review |
DescriptionThe DQ400E transmission control unit stores P17BF when it detects the following condition: Hydraulic pump system overload protection. The fault concerns the hydraulic supply of the mechatronic unit. The control unit compares the required system pressure with the measured pressure and stores the code when the pressure is too low, too high, builds up too slowly, or the pump runs outside its normal operating time. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P189C | Function restriction — insufficient pressure build-up | Hydraulic pressure | Review |
DescriptionThe DQ400E transmission control unit stores P189C when it detects the following condition: Function restriction — insufficient pressure build-up. The fault concerns the hydraulic supply of the mechatronic unit. The control unit compares the required system pressure with the measured pressure and stores the code when the pressure is too low, too high, builds up too slowly, or the pump runs outside its normal operating time. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P2711 | Unexpected mechanical gear disengagement | Gear ratio / gear loss | Review |
DescriptionThe DQ400E transmission control unit stores P2711 when it detects the following condition: Unexpected mechanical gear disengagement. This is a mechanical plausibility check: the control unit compares the input and output shaft speeds with the ratio expected for the selected gear. The code is stored when the calculated ratio does not match or a gear drops out unexpectedly. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| P2884 | Engine disconnect clutch K0 — stuck open | Clutch faults | Review |
DescriptionThe DQ400E transmission control unit stores P2884 when it detects the following condition: Engine disconnect clutch K0 — stuck open. The fault concerns clutch control: engagement, adaptation, torque limitation or clutch temperature. The control unit compares the commanded clutch position or pressure with the measured value and stores the code when the difference or the adapted value leaves the permitted range. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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| U0101 | Lost communication with TCM | Communication | Review |
DescriptionThe DQ400E transmission control unit stores U0101 when it detects the following condition: Lost communication with TCM. The fault concerns data communication between the transmission control unit and other control units on the powertrain CAN bus. The code is stored when messages are missing or corrupted, or the bus hardware reports an error. A stored code does not by itself prove that a part has failed. Before replacing anything, check the live data, wiring, connectors, power supply and fluid condition, and confirm the fault on the vehicle. Symptoms
Possible causes
This code is documented but not independently confirmed. Confirm it against the specific vehicle before ordering any part.
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Related pages for the DQ400E
DQ400E repair
Symptoms, mechatronic issues and what repair involves for this family.
DQ400E mechatronics
Replacement mechatronic unit and exchange options for this family.
DQ400E parts
Selected parts most often involved in repair for this family.
DQ400E fault codes
Every documented code for this family in one table.
DQ400E parts questions
Are DQ400E parts interchangeable with other DSG families?
Generally no. The hydraulic design, clutch type and electronics differ between families, so parts are listed per family and should be matched to the correct one.
How do I know whether I need a part or an assembly?
It depends on the fault. Send us the fault codes, the symptoms and the part number and we will confirm which approach applies to your DQ400E.
Do you supply the mechatronic assembly as well as parts?
Yes. Replacement mechatronic assemblies for the DQ400E are listed on the DQ400E mechatronics page.
Have a DQ400E part number?
Send us the part number and the vehicle details and we will confirm the correct DQ400E part by email.