Mail-In Unlock: Bosch MG1CS031 & MG1CS142 (VAG 2.0T EA888.4 LK1)

Start tuning now! Get your Bosch MG1CS031 and MG1CS146 ECU unlocked right here in the USA with our quick and convenient mail-in unlocking service with same-day turnaround. This unlock supports Bench with the AT Tool complete with full Bootloader+ASW+Calibration read on the 2.0T Audi, Seat, Skoda, Cupra, and Volkswagen Models!

Unsure if your vehicle is supported?
Search our guide!

Sale price$399.00

⚠️ Do not open the ECU case. It's not needed.

Next Day Air (Both Ways)

Shipping, both ways, is calculated at checkout. We will email you a shipping label during normal business hours (M-F, 8-5 CT).

Mail-In Only

We support mail-in unlocks only. In-person service isn’t available at this time. If you send an AirTag, tape it to the ECU.

📦 Fast and secure shipping with UPS Next Day Air

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What's supported?

Supported ECU

  • Bosch MG1CS031 TC298
  • Bosch MG1CS142 TC387

To confirm compatibility, perform a Bench Identification using an AutoTuner tool.

US Compatible Models

  • 2022+ Audi A3 (8Y.x) 2.0T EA888.4 LK1 201 HP MHEV (40 TFSI)
  • 2021+ Audi A4 (B9.x) 2.0T EA888.4 LK1 201 HP MHEV (40 TFSI)
  • 2021+ Audi A5 (B9.x) 2.0T EA888.4 LK1 201 HP MHEV (40 TFSI)

Global Compatible Models

  • Audi Models: A1 (2018+) / A3 (2019+) / A4 (2018+) / A5 (2019+) / Q2 (2021+) / Q3 (2018 – 2025+) / Q5 (2017+) / TT (2018+)
  • Cupra Model: Formentor (2020+)
  • Seat Models: Ateca (2020+) / Leon (2020) / Tarraco (2019+)
  • Skoda Models: Karoq (2022+) / Kodiaq (2023+) / Octavia (2020+) / Superb (2019 – 2023+)
  • Volkswagen: Arteon (2020+) / Golf (2020+) / Passat (2019+, 2023+) / Polo (2021+) / T-Roc (2017+) / Tiguan (2021+, 2024+)

Supported Engines

  • 2.0T EA888 Gen 4 (LK1 ≤ 150 kW / 204 PS / 201 HP)
  • 2.0 TSI / EU6 / 35 TFSI / 40 TFSI

Please Note: Compatible vehicles will list, at a minimum, the Bosch MG1 ECU version on the ECU ticker. This does not cover the Continental Simos 19.x ECUs found in vehicles such as the latest facelifted MK8.5 GTI, Golf R, S3, Etc.

Think something's missing? Search our more comprehensive guide!

How does this work?

Step 1

Mail us your ECU

  1. Purchase the unlock. 
  2. Remove the ECU(s).
  3. Ship it to us.

We make shipping easy: We send you the shipping label for UPS Next Day Air at phenomenal rates. Just drop it off at any UPS access point.

You'll receive the shipping label during our normal M-F, 8-5 Central business hours.

Not sure if it's locked? An AutoTuner Tool will tell you. Some cars have two ECUs so you'll need to purchase an unlock for both. If we require the case to be opened, we'll let you know!



Step 2

We'll unlock it and mail it back

Our trained professionals run each ECU through a secure, proprietary unlocking process. The exact methods are confidential as revealing them could risk future manufacturer lockouts. 

All AutoTuner USA unlocks are unlocked same day in the USA and we don't physically modify the ECU. We ship it back next UPS Next Day Air.

We process ECUs during normal business hours: M-F, 8-5 Central.

*Pic unrelated

Step 3

Time to have fun

With your unlocked ECU in hand, reinstall it and get down to tuning.

FAQ

Still have questions?

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