Mercedes-Benz Car Key Replacement in Hamilton

EIS (Electronic Ignition Switch, older Mercedes): The EIS module controls key recognition on W203 C-Class, W211 E-Class, ML W163/W164 and similar models. Programming a replacement key on an EIS-equipped Mercedes requires coding a new key to the EIS and ensuring the EIS remains properly synchronised with the ECU and transmission control unit. This is sensitive work — the EIS on some older Mercedes models is notoriously fragile.

KESSY (Keyless Go, 2007–present Mercedes): KESSY is Mercedes' proximity entry and push-button start system. The smart key communicates with multiple antennas around the vehicle body. Programming a new KESSY key requires Mercedes-level diagnostic access to the EZS (Electronic Ignition Lock) module and the vehicle's security seed. We cover KESSY programming for most NZ-market Mercedes models.

NTG-based infotainment integration: On current-generation Mercedes (W213 E-Class, W205 C-Class, GLE, GLC), the key system is integrated with the vehicle's multimedia platform in ways that require a correctly sequenced programming process. We work through these correctly — there is no shortcut.

Mercedes Sprinter van keys: The Sprinter commercial van uses a separate key platform from the passenger car range. We cover Sprinter key programming — both older 906-generation and current 907-generation models.

KESSY key not detected: The Mercedes pushes a small LED indicator when the key is placed in the start well — if the LED does not activate, the key is not being detected. Most common cause: flat key battery (specific to your MB variant — CR2025 or CR2032). We carry both. If battery replacement does not fix it, the key may need re-pairing.

EIS faults on older Mercedes: Older W203 and W211 models develop EIS faults where the key turns but the vehicle does not respond correctly — sometimes an intermittent fault, sometimes a complete failure. We diagnose EIS-related faults and advise honestly on whether the EIS module itself needs attention.

Mercedes key fob wear and damage: Mercedes smart key fobs — particularly the flip-key design used on many W204 and W212 models — develop hinge failure and button wear. We rebuild these where the circuit board is undamaged.

Sprinter van lockouts: Mercedes Sprinter vans in Hamilton's trades and courier sector get locked out regularly. Non-destructive entry for Sprinter cargo vans is standard procedure.

• C-Class (W204, W205, W206) — EIS and KESSY programming across generations; very common in Hamilton
• E-Class (W211, W212, W213) — EIS and KESSY; we advise on model-specific complexity before travel
• A-Class and B-Class — smart key programming for current models
• GLC and GLE — KESSY smart key programming
• GLA and GLB — current-generation smart key
• Sprinter (906 and 907) — commercial van key programming; fleet rates available
• ML-Class and GL-Class — older models covered; EIS sensitivity noted
• CLA and CLS — smart key programming