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Mercedes-Benz C-Class OBD port location

Five generations, 2001–2024. Pick yours.

2021–2024

W206

Illustration — use it to know where to look.

Location

Driver's side footwell, under the lower dashboard, to the left of the steering column and beyond the bonnet release lever. Small snap-off plastic cover must be removed by hand — no tools required. On right-hand drive (UK) vehicles the port is set further back than expected: follow the underside of the dashboard past the bonnet release lever and the port is behind a cover slightly to the left of centre. Consistent with the preceding W205 — same dashboard zone and cover type confirmed by Mercedes forum guidance for W206.

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Open the full C-Class W206 record

2014–2021

W205

Illustration — use it to know where to look.

Location

LHD: Driver's footwell, beneath the lower dash trim to the left of the steering column. Follow the line of the bonnet release lever inward and slightly up — the 16-pin socket sits behind a small snap-off plastic cover near the bonnet release, set well back under the dash. RHD (UK): Mirror image — driver's footwell, well back under the dash beyond the bonnet release and a little to the left of it, behind the same small cover. On both sides the socket is set deep and angled upward; a torch helps. Same location across all W205 trims (saloon, estate, coupe, AMG) and across the 2018 facelift.

Also on this C-Class

  • KeysSmart key
  • Tools confirmed12
  • Transponder chipSubscribers
  • Programming procedureSubscribers
Open the full C-Class W205 record
OBD port location in a Mercedes-Benz C-Class W204 facelift

W204 facelift (Mopf) 2011–2014

RHD (UK): driver's footwell, under the lower edge of the dashboard on the right-hand side of the steering column, roughly above the driver's right knee and immediately alongside the bonnet-release lever. Sit in the seat, drop your head to knee height and look up and outboard — it is the same socket the main dealer plugs into. LHD: mirror image, under the lower dash to the left of the steering column, again next to the bonnet release. Same position on saloon, estate and coupé, and the same on AMG cars — only the amount of room around the knee bolster changes.

OBD port location in a Mercedes-Benz C-Class W204

W204 (saloon) 2007–2014

RHD (UK): driver's footwell, under the lower edge of the dashboard on the right-hand side of the steering column, roughly above the driver's right knee and immediately alongside the bonnet-release lever. Sit in the seat, drop your head to knee height and look up and outboard — it is the same socket the main dealer plugs into. LHD: mirror image, under the lower dash to the left of the steering column, again next to the bonnet release. Same position on saloon, estate and coupé, and the same on AMG cars — only the amount of room around the knee bolster changes.

North American models

OBD port location in a Mercedes-Benz C-Class W203

W203 (saloon) 2001–2007

LHD (every US car): driver's footwell, under the lower edge of the dashboard to the left of the steering column, directly above the pedals and immediately beside the bonnet (hood) release handle — find the hood release first and the socket is just to its right. Sit in the seat and look up under the dash at knee height. Same position on the saloon, the wagon and the Sport Coupé, on every engine, and it did not move at the MY2005 facelift. There is no 38-pin round diagnostic socket on the 203; the 16-pin OBD socket is the one every key tool and the dealer system use.

Questions

Mercedes-Benz C-Class OBD questions

W206 (2021–2024): Driver's side footwell, under the lower dashboard, to the left of the steering column and beyond the bonnet release lever. W205 (2014–2021): LHD: Driver's footwell, beneath the lower dash trim to the left of the steering column. W204 facelift (2011–2014): RHD (UK): driver's footwell, under the lower edge of the dashboard on the right-hand side of the steering column, roughly above the driver's right knee and immediately alongside the bonnet-release lever. W204 (2007–2014): RHD (UK): driver's footwell, under the lower edge of the dashboard on the right-hand side of the steering column, roughly above the driver's right knee and immediately alongside the bonnet-release lever.

Other Mercedes-Benzs

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Step-by-step add-key and all-keys-lost procedures for every C-Class, which of your tools will do it, and what catches people out.

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