Since roughly 2021 a growing share of Bosch MDG1 engine controllers leaves the factory in a state the tool manufacturers call “locked”. On a tractor or combine that means the familiar routine – plug into the diagnostic socket, read, write – stops at the first step, and so does the bench protocol. This page explains what is locked, which machines are affected, and the two unlock routes that Alientech and Autotuner published in 2026. It is written for dealers and workshops that already own one of the two tools.

What “locked” means in practice

The MDG1 generation (MD1CE101, MD1CS069, MD1CS089, MD1CE100 and relatives) runs on Infineon TC29x and TC39x processors. On the locked variants the manufacturer’s security configuration no longer allows the diagnostic session the tuning tools used until then, and the bench connection runs into the same closed door. Neither tool manufacturer publishes the technical detail of what exactly is closed – both simply list the affected units as “Locked” and publish a separate path for them.

Three things follow from that. First, a locked controller is not broken and not “protected by the dealer” – it is the production state. Second, the standard OBD and bench protocols for the same ECU name still work on the earlier, unlocked units, so the model year decides, not the ECU label. Third, the unlock is a one-time preparation of the controller; once done, the normal protocols apply.

Which machines are affected

The published lists overlap heavily because the same FPT, Deutz and AGCO engines sit under many brands. From the release notes of October 2026:

Which of these a given machine actually has is a question of production date and engine variant, so identify the controller on the machine before quoting anything.

Route 1: Alientech KESS3 Unlock Module

Alientech released a dedicated accessory in September 2026, the KESS3 Unlock Module, and in October added the locked MD1CE101 to it. The procedure is a boot-mode job in the workshop: the controller is opened, connected in boot and unlocked with a patch. After that the existing OBD and bench protocols for the ECU apply, and the unit does not have to be opened again for later work (accessory release note, MD1CE101 release note).

• What you need: KESS3 with the agriculture / truck bench-boot protocols active, the Unlock Module, an active subscription, a boot frame and a stable bench power supply.
• Time on site: the machine stands still for the length of one boot session; nothing is sent away.
• What you get: a full boot read, which doubles as the complete backup of the controller before any file goes in.
• Where it stops: the published list is FPT-engined machines from 2021 for the MD1CE101; the MD1CS069 is on the accessory’s list, the car and van brands dominate that announcement.

Route 2: Autotuner mail-in unlock

Autotuner takes the opposite approach: the controller is sent to one of their unlock centres (Europe and the US), prepared there and returned. Published terms for Europe are a flat 250 euro, work within 24 hours of arrival and a typical two to three days including transport. Opened units and units with damaged connector pins are excluded. The service started in mid-2025 with MD1CS069 and MD1CS089 and, since September 2026, is also the entry ticket for the MD1CE100 / MD1CE101 bench protocol, which covers the Case IH, New Holland, Steyr and Claas lines as well as MAN, Fendt 700 Vario from 2022 and Doosan construction equipment (release note).

• What you need: an Autotuner tool, the optional bench cable for the ECU family, and a plan for two to three days without the machine.
• Time on site: none for the unlock itself, but the controller has to come out and go back in.
• Backups: Autotuner creates automatic backups on bench and boot reads, not on OBD reads – take the bench read after the unlock and keep it.
• OBD afterwards: the September 2026 OBD protocol for MD1CS069 / MD1CE101 is a beta and reads in about eleven minutes; the release note does not say which production years it reaches without the unlock, so test on the first machine of each type before promising port access to a customer.

Choosing between the two

Neither manufacturer documents what the preparation changes inside the controller, how a later dealer software update behaves on an unlocked unit, or whether the state can be reversed. Treat the unlock as a permanent change to the controller, record the serial number and the original read in the job file, and tell the customer.

What goes in the file afterwards

The unlock only opens the door. The calibration work on MD1CE101 and MD1CS069 is the same as on the earlier units – Stage 1, DTC handling and the emission-related solutions we release per ECU. Our Bosch MD1CE101 page covers the platform, and the machine lists with tool access per model are under Case IH, New Holland, Claas and MAN.

Frequently asked questions

Can I tell from the ECU label whether it is locked?

No. The label reads MD1CE101 on both generations. The production year of the machine and the tool’s identification tell you; the tools report a locked unit when the standard protocol is refused.

Does the unlock change the engine software?

Both routes prepare the controller so that it can be read and written; the calibration itself is untouched until you write a file. Keep the first full read as the reference original.

Is this the same as “glitching”?

Workshops often call the boot-level procedure glitching. The manufacturers use “boot unlock” and “unlock service”, and that is the wording you will find in their release notes and price lists.

Which route do you recommend?

If you already own KESS3 with the off-highway packs and do boot work regularly, the module keeps the machine in your yard. If you run Autotuner, the mail-in service is the published path and the cost is predictable; plan the downtime with the customer. We work with files from both.