Mercedes CLA C117 7G-DCT TCU Cloning by Post UK — A0054463310 P1890 P1872
Mercedes CLA C117 7G-DCT TCU Cloning by Post UK — A0054463310 / A0054463710 | P1890 P1872
Your CLA has thrown fault codes P1890, P1872 or something in the P17XX family, the gearbox is behaving erratically or refusing to select gears normally, and your diagnostic tool is pointing at the transmission control unit. That is a TCU communication or calibration failure — not always a mechanical gearbox problem — and in many cases the fix is TCU cloning, not a full gearbox replacement. The Vehicle Check clones the 7G-DCT TCU for the Mercedes CLA C117 by post, nationwide, with a 3–5 day turnaround and free tracked return.
Quick Facts
| Detail | What you need to know |
|---|---|
| Service | 7G-DCT TCU cloning — Mercedes CLA C117 |
| Part numbers covered | A0054463310 & A2C73939004 (5-pin), A0054463710 (4-pin) |
| Fault codes addressed | P1890, P1872, P17XX family |
| Service type | Cloning only — your data transferred to a known-good unit |
| Turnaround | 3–5 working days from receipt |
| Return shipping | Free tracked courier |
| Coverage | Nationwide UK mail-in; international enquiries welcome |
| How to book | Call 0203 489 2610 or use the contact form at thevehiclecheck.co.uk |
| Workshop location | Office 13, 25 Mollison Avenue, Enfield, EN3 7NJ |
What do fault codes P1890, P1872 and P17XX actually mean on the CLA C117?
These codes live in the transmission control module and typically indicate a loss of internal calibration, corrupted stored data, or a failure in the TCU's ability to communicate with the dual-clutch gearbox hardware. P1890 is commonly logged as a clutch adaptation or pressure-regulation fault. P1872 often relates to gear-selection or solenoid-circuit communication. The broader P17XX family covers transmission range, sensor plausibility and general TCU integrity errors. When the TCU's internal data is compromised, you may see the gearbox stuck in a single gear, refusing to shift, shuddering on pull-away, or the car entering a limp-home programme. Cloning transfers the correct configuration from a known-good donor unit onto a healthy control module, restoring the values the gearbox expects — without buying a new unit from Mercedes at main-dealer prices.
Which TCU part numbers does TVC cover for the 7G-DCT CLA C117?
TVC works with the following unit-family numbers for the CLA C117 7G-DCT:
- A0054463310 and A2C73939004 — 5-pin connector variant
- A0054463710 — 4-pin connector variant
These are unit-family references. The number printed on the label of your specific TCU may differ slightly depending on build date or revision level. Always check the label on your own unit and confirm with TVC before sending — they will verify the number and tell you whether your unit is within scope before any work starts. Call 0203 489 2610 or drop a message through the website if you are unsure.
Is mail-in TCU cloning better than going to a Mercedes dealer?
| Factor | TVC mail-in cloning | Mercedes main dealer |
|---|---|---|
| What happens to your data | Cloned and preserved — car recognises unit as original | New unit often needs full programming and adaptation |
| Turnaround | 3–5 working days | Parts lead times often 1–3 weeks or longer |
| Need to attend in person | No — post unit from anywhere in the UK | Yes — car must be present at the dealership |
| Return shipping | Free tracked courier included | N/A — collection only |
How do I send my CLA C117 TCU to TVC safely?
Getting the unit to TVC safely is straightforward. Here are some practical tips:
- Remove the TCU carefully — disconnect the battery first and allow at least 5 minutes before unplugging the connector. If you are not confident doing this yourself, any independent garage can remove it for you in under 30 minutes.
- Check the connector pins — count the pins on your unit (5-pin or 4-pin) and note the part number from the label before you pack it. Send TVC a photo of the label when you book.
- Wrap in bubble wrap — place the unit in a zip-lock bag first to protect connector pins, then wrap in at least two layers of bubble wrap. Avoid loose packing peanuts that can shift and cause pin damage.
- Use a rigid box — a double-walled cardboard box is ideal. Do not post the unit in a padded envelope.
- Use a tracked service — Royal Mail Special Delivery or a named courier such as DPD or DHL. Keep your tracking number until the job is complete.
- Include a note inside — your name, phone number, vehicle registration and the fault codes or symptoms you have seen. This helps TVC get straight to work on arrival.
Send to: Office 13, 25 Mollison Avenue, Enfield, EN3 7NJ.
Why trust TVC with your CLA's transmission electronics?
The Vehicle Check is a UK automotive electronics specialist that has been bench-testing, cloning and restoring transmission and body control modules across a wide range of European and Japanese vehicles for years. The team works daily with Mercedes mechatronic and TCU units, VAG DSG mechatronics, clutch actuators, body control modules and crash-data modules — not as a sideline, but as the core of everything they do. If you want to see the broader range of transmission work TVC handles, the mechatronic repairs collection gives a clear picture. For other automotive electronics, TVC also covers clutch actuator repairs, BCM, BSI and FRM cloning, and crash data and airbag module reset.
Frequently asked questions — CLA C117 7G-DCT TCU cloning
Ready to send your CLA C117 TCU? Here is how to get started
Call TVC on 0203 489 2610 or use the contact form at thevehiclecheck.co.uk to confirm your part number and get the green light before you post. Once confirmed, pack the unit safely using the guidance above, ship it tracked to Office 13, 25 Mollison Avenue, Enfield, EN3 7NJ, and TVC will have it cloned and back with you within 3–5 working days — free tracked return included. No main-dealer wait, no need to take the car anywhere.
⚠️ Warranty Terms for This Repair
- Our 12-month warranty on this repair is conditional on a full transmission oil and filter change being carried out at the time of refitting.
- Please keep proof of this — a paid invoice from a garage or workshop — as this will be requested if you ever need to make a warranty claim.
- This is a transmission component, and correctly completing the fit requires the correct basic settings, adaptations and teach-in procedure for your specific gearbox to be carried out afterwards for it to operate correctly.
- Many owners with the right diagnostic equipment and experience fit these themselves — that's completely fine. If you're doing the oil/filter change yourself rather than at a garage, keep your own dated records (receipts for the oil/filter, and confirmation the adaptations were completed) as equivalent proof for a claim.
The Vehicle Check is a UK automotive electronics specialist at Office 13, 25 Mollison Avenue, Enfield, EN3 7NJ, offering nationwide and international mail-in repair and cloning. Call 0203 489 2610. Last updated: 7 November 2026.