Star3 SECoC coding
SECoC commissioning, ZenZefi certificates, and timeback for the newest Mercedes chassis - W206, W223, X254, EQE, EQS. We run the full Star3 backend so partners can code, re-sign, and teach in modules on Gen20x cars end to end.
The newest Mercedes chassis don't let you code anything without an online certificate with ZenZefi. W206, W223, X254, EQE, EQS - every variant write, every module swap, every teach-in has to be signed by Mercedes' servers in real time. Xentry Pass-Thru with a local licence isn't enough on its own.
This page is for workshops and partners who keep getting blocked by that wall. We run Star3 with SECoC commissioning and ZenZefi certificates live on the wire, so you can code a W223 the same afternoon the owner drops it off.
What SECoC actually is
SECoC is Secure On-board Communication. Mercedes introduced it on MBUX Gen 2 / Gen20x to stop unsigned writes landing on the CAN and DoIP buses. Every coding transaction carries a rolling cryptographic signature. The ECU checks the signature against a fresh key before it commits anything to flash. Wrong key, expired key, drifted clock - the ECU drops the frame and the job fails halfway.
ZenZefi is the certificate manager that distributes those keys. It fetches the right certificate for the job and hands it to the diagnostic tool. Without a working ZenZefi pipeline you can see the modules but you can't write to them.
Which cars need this
The short list, as of the current chassis lineup:
- W206 C-Class (2021+)
- W223 S-Class and Maybach S-Class (2020+)
- X254 GLC (2022+)
- V295 EQE and EQE SUV
- V297 EQS and EQS SUV
- W232 E-Class (2024+)
- W214 E-Class from mid-production
- C296 Maybach EQS SUV
- Any Gen20x refresh of the GLE, GLS, and G-Class on the new electrical platform
If your car has Zero-Layer MBUX and a Gen20x headunit, assume SECoC is in the way.
What we run for partners
A working Star3 instance on our side, with:
- Live SECoC commissioning on every ECU that asks for it - central gateway, body modules, ADAS stack, drivetrain, headunit, charging hardware on EQ cars.
- ZenZefi certificate for 2026 coding (Aftersales Enhanced), and programming certificates for actual variant coding (Development Enhanced).
- Timeback - Vehicle unlock for coding.
- Full SAS variant coding, SCN, teach-in, and component protection handling where the VIN and SA codes allow it.
- Read-back verification after the write, plus a cold-start sanity check so you don't close a ticket on a module that fails to come up after ignition off.
Typical jobs we cover
- AMG menu unlocks, Digital Light activation, ambient tier upgrades on W223 and W206.
- Module replacement after a crash or a theft recovery: gateway, FSCM, BCM, instrument cluster.
- Regional conversions on Gen20x imports where the destination market allows it.
- Post-repair SCN and teach-in on EQE and EQS, including charging module re-signs.
- Retrofit coding on factory-wired but disabled options (head-up display, rear-axle steering, Burmester tiers).
If a job needs SECoC and you can't run it on your own bench, we can run it with you.
How a partner session runs
Contact us for procedures.
What you need on your side
- An ENET yellow cable with the MB pinout. If you aren't sure which one you have, the VCI guide walks through it.
- A Windows 10 or 11 laptop with a wired internet connection for the duration of the session. Laptops going to sleep mid-signing is the single most common reason a job has to be restarted.
- The car at 13.5 V or better. A weak 12 V battery on a W223 will drop the gateway mid-coding.
- Ignition on, no active DTCs on the gateway before we start.
Pricing and partner terms
Pricing is per-job for one-off tickets and volume-based for shops running SECoC work every week. Partner accounts get priority scheduling, a direct line into the team, and an API option for high-volume workflows. Billing is per month, invoiced.
We don't publish the partner rate card openly. Email with your shop name, country, and the chassis mix you see most and we'll send it back the same working day.
Contact
- Email contact@mbretrofit.it with subject line Star3 SECoC partner access.
- Include: shop name, country, rough monthly volume of Gen20x coding jobs, and whether you already run Xentry locally.
- Prefer a call first? Say so in the email and we'll book one.
If you're a single-car owner rather than a workshop, the standard remote-coding flow on the vehicle coding overview covers one-off W206 and W223 jobs without the partner contract.
Enter your VIN to generate your Mercedes‑Benz map license key. Works with supported NTG systems.
Use coupon PRESUMMER for 10% off. Expires Jan 1st.
Vehicle Connection Interfaces (VCI)
Pick the right OBD cable for your Mercedes coding job. We match your VIN to the cable your chassis actually needs - Openport for CAN, ENET + AT adapter for DoIP.
Region Conversion
Convert a US, JP, CN, or GCC-spec Mercedes to EU spec (or the other way around). Cluster units, headlight beam pattern, DRL behaviour, ambient lighting, MBUX language packs, and navigation map region - all handled in coding and map licensing. Contact us for a VIN-specific quote.