Programming & Coding
of Car Keys via OBD

Since about 1995 (European directive on the electronic immobiliser), practically no car sold in Europe can start without electronic authentication of its key. The mechanical blade is still used to open the door in most cases, but engine start depends on a cryptographic dialogue between three elements: the transponder embedded in the key, the immobiliser antenna around the ignition lock cylinder (or around the start button), and the central ECU (ECU, BSI, BCM, FEM/BDC depending on the brand).

This authentication has evolved across four generations. The first — Megamos crypto, Philips ID33, ID40 — dating from the 1990s, is now obsolete and easily cloneable. The second (ID4A, ID46) dominated the 2000-2015 period and remains the core of our business: Peugeot, Citroën, Renault, Ford, VW group, Toyota… The third (ID48 fixed and rolling) introduced 96-bit encryption with rolling code, present on the VW Golf VI/VII, Audi B8, Skoda Octavia III. The fourth, in place since 2018, uses AES-128 (military-grade encryption) and applies to everything recent: Renault Captur II, Mégane IV, Tesla, BMW F40/G20, Mercedes W213.

For each generation, the new key registration protocol is different. On a Renault ID46, we work directly on the BSI via the K-Line API; on a Renault AES, you have to go through reading the BCM dump and calculating the cryptographic keys via a proprietary algorithm (often assisted by an Autel/Abrites online server). Intervention times reflect this growing complexity.

Key registration is anything but universal. Each manufacturer group has developed its own OBD dialogue, its own PIN format (sometimes calculated from the VIN, sometimes stored in EEPROM, sometimes generated online by the manufacturer server), and its own authentication rules. Here is what we handle daily:

On some very recent protocols (Mercedes FBS4, BMW BDC2 G20, Renault AES on Captur II), registering a new key may require a connection to a manufacturer online server (Mercedes XENTRY Pass-Thru, BMW ISTA, Renault CLIP After Sales). We hold the required professional accesses. Exceptional case: armoured vehicle or with custom immobiliser (Mercedes Maybach Guard) — specific quote.

1. 1 Preliminary phone diagnosis 5-10 min You tell us the make, the exact model, the year and the type of key required (mechanical with transponder, key fob, Hands-Free card). We identify the protocol, any PIN to calculate, and the equipment to bring. Firm quote communicated verbally before travel.
2. 2 Identity and ownership verification 5 min The technician checks your ID and the vehicle registration document. No programming is performed without being able to verify that you are the owner or an authorised party. This is a legal requirement of the Security Code and a DKP insurance requirement.
3. 3 Immobiliser read and preparation 10-30 min Connection to the OBD port (typically under the steering wheel or in the centre console). Module identification (BSI, BCM, FEM/BDC, EIS…), PIN extraction or EEPROM read if required. On recent AES protocols, dialogue with the manufacturer online server for cryptographic key calculation.
4. 4 Key registration 5-25 min Programming of the transponder in the immobiliser table, pairing of the remote radio frequency, synchronisation with the BCM for central locking. Verification that all functions respond: engine start, remote lock/unlock, alarm, boot opening via key fob.
5. 5 Tests, invoice, handover 5-10 min Three complete start/ignition-off cycles, test of all radio commands, verification that previous keys remain functional. Issue of the named tax-inclusive invoice. Payment by card, cash, instant transfer. Handover of the keys and signature of the intervention voucher.