P0805 – VW DSG Mechatronic Control Unit Fault

Have you been shown the dreaded ‘gearbox in emergency mode’ message in a DSG-equipped VW, and you’ve found a P0805 code stored too? This is a key indicator that your DSG mechatronic control unit has failed. But don’t worry, this isn’t as costly as it sounds – we remanufacture these units for much less than the cost of a brand-new one.

Shop Now – VW Tiguan P0805 Solution

If you’re experiencing this, you’ll no doubt have a transmission warning light on too and you might have completely lost one set of gears – this is a common issue for the DQ381 DSG. These symptoms typically emerge after prolonged driving and they stem from an internal malfunction of your DSG’s mechatronic unit. 

If your Volkswagen is experiencing DSG issues and you’ve found a P1735 or P1736 code stored rather than P0805, we can resolve this too – get started by completing our test form.

Which VW models are affected by the P0805 DSG fault?
The P0805-causing defect is a major issue for the DQ381 DSG. These gearboxes are fitted to a wide range of VAG models, including many Volkswagens like the second-generation Tiguan (2016-2021) and the Mk7 Golf (2017-2021).

The DQ381 is fitted to vehicles with engines sized 2.0L or less, and manufactured after 2016. Thankfully, we remanufacture most DSG mechatronic units for a range of faults, browse our product catalogue for our full range.

What causes the VW P0805 DSG fault?
As already mentioned, an internal defect within your DSG mechatronic unit is preventing it from functioning properly and leaves behind a particular fault code:

• P0805 – Clutch Position Sensor “A” Circuit

You might already know that these are hydro-electric control units that are responsible for dictating clutch and gear engagement, helping to create a smooth and seamless shifting experience. However, when these intricate control units go wrong, they can cause monumental issues for owners.

In the case of your DQ381’s P0805 issue, the TCU within your mechatronic unit is receiving an implausible reading from one of the clutch sensors. This occurs due to internal degradation of the mechatronic, which as you can imagine, greatly disrupts the operation of these finely-tuned units. 

In short, a P0805 code indicates the DSG’s TCU can no longer reliably tell whether the clutch is responding to its commands – hence you lose whichever set of gears said clutch is responsible for. As a result, the TCU puts the DSG into emergency mode to mitigate damage, illuminates the transmission warning light and stores codes like P0805.

How to resolve your VW’s P0805 fault
When met with a P0805 fault code and accompanying transmission-related symptoms, many owners are advised to have their DQ381 mechatronic replaced. However, this leaves you vulnerable to repeat malfunction and it’s certainly not the most cost-effective solution.

As mentioned, these control units fail and store P0805 as a result of internal component degradation. The reason this is so common is because the internal components in question aren’t durable and often fail after just a few years.

Therefore fitting a like-for-like replacement mechatronic to your VW runs the risk that your DSG will fail and store P0805 again in exactly the same way as before. Fortunately, we’ve developed a more-affordable and much-longer-lasting solution.

Our VW P0805 solution
Rather than sourcing an expensive replacement, we propose having your mechatronic unit professionally remanufactured by us.

We analyse these units on bespoke hardware-in-the-loop testing rigs, which replicate realistic operating conditions. This allows us to uncover hard-to-find faults and pinpoint the root cause of failure with confidence and accuracy. 

Our team of expert technicians will then get to work rebuilding your mechatronic unit with higher-than-OEM-standard components. This way, functionality is not only restored now, but it’s restored for good. We’ll even cover your rebuilt mechatronic unit with an unlimited-mileage lifetime warranty.

Our tried-and-tested P0805 solution costs much less than sourcing a brand-new DSG mechatronic, and you won’t need to recode it back to your VW after we’ve finished.

Resolve your Volkswagen’s P0805 code the long-lasting way, have your DQ381 DSG mechatronic remanufactured by the experts – just fill out our test form to begin.

Common failure symptoms:

• Transmission warning light on
• Engine warning light on
• Rough gear changes
• Loss of one set of gears (odd or even)
• ‘Gearbox in emergency mode. You can drive on.’ Message on dashboard
• Reverse gear unavailable

Common fault codes:

• P0805 – Clutch Position Sensor “A” Circuit
• P1735 – Position Sensor For Clutch 1: Electrical Malfunction
• P1736 – Position Sensor For Clutch 2: Electrical Malfunction
• P175D – Clutch 1 Opens Unintentionally 
• P175E – Clutch 1 Closes Unintentionally

Removal/refitting guide:

Test and rebuild:
We use bespoke testing rigs to analyse DQ381 mechatronic units, allowing us to test under realistic operating conditions. Once the malfunction has been confirmed and verified, we’ll rebuild your control unit with top-grade components that provide long-term durability. 
 
Programming:
You won’t need to reprogramme your mechatronic unit back to your DQ381 or vehicle after we’ve finished with it.
 
Quality:
We operate under strict quality control procedures which have contributed to our industry-leading defect rate of 0.49%. Thanks to this, we have become the chosen provider of ECU remanufacturing services for thousands of industry specialists worldwide.

Warranty:

Lifetime unlimited mileage*

How do I get my unit rebuilt?

To pay for the rebuild click the Shop Now link above, select your part number and click: Get yours rebuilt.

Print the payment/booking confirmation email.

Package the DQ381 mechatronic inside a sturdy box with plenty of packaging material and make sure you include your confirmation email in the box.

Send us your package by tracked courier (the shipping instructions are on the confirmation email).

Once received we will test, rebuild and return your unit with an unlimited mileage lifetime warranty. If your unit turns out not to be faulty then we will refund your payment less a small testing fee and return shipping.

What if I don’t want to pay up front?

This is not a problem, if you prefer this option then follow these steps:

Fill in and submit this test form.

Print the booking confirmation email.

Package the mechatronic inside a sturdy box with plenty of packaging material and make sure you include your confirmation email in the box.

Send us your package by tracked courier (the shipping instructions are on the confirmation email).

Once received, we will test your control unit and call to inform you of the outcome of testing. If your DQ381 is faulty and you choose to go ahead with the rebuild, then we will take payment over the phone using a debit/credit card.

We will then rebuild your control unit and return it to you with an unlimited mileage warranty.

If you require further information regarding this P0805 DQ381 fault then please contact us.