P0205 on Mercedes-Benz: Causes, Symptoms and Fix Cost
Quick Answer
Safe to drive (short-term)
P0205 on a Mercedes-Benz means the engine control unit has detected an open, a short or an out-of-range resistance in the cylinder 5 injector circuit. The code only exists on engines with five or more cylinders: inline-fives, inline-sixes, V6s and larger. Where cylinder 5 sits depends on the layout, from the gearbox end of an inline-five to either bank of a V6. A wiring repair typically costs about 65-220 EUR at a workshop; a petrol injector fitted about 100-310 EUR.
- Severity
- Moderate · Fuel System
- Typical repair cost, all makes
- €5-€650
Connect a standard OBD2 adapter (Bluetooth LE on iPhone) to your Mercedes-Benz and Skanyx tells you what P0205 means on that engine, whether it is safe to keep driving, and what the fix should cost. Free on iPhone and Android.
Get Skanyx freeWhat does P0205 mean on a Mercedes-Benz?
The Quick Answer above is the generic definition. What follows is the model-specific detail for the Mercedes-Benz models that log P0205.
Mercedes C-Class
2007-2024
V6 petrol (M276) and V6 diesel (OM642) C-Class variants have a cylinder 5. The OM642 diesel uses costly common-rail injectors with calibration codes that must be written via XENTRY or a workshop after replacement. Petrol variants usually fault from a corroded connector or chafed harness.
What causes P0205 on a Mercedes-Benz?
Beyond the generic causes listed on the main P0205 page, these are the patterns noted for Mercedes-Benz models:
Common-rail injector with calibration coding on OM642 V6 diesel
: Mercedes C-Class
Connector corrosion or harness chafe on M276 V6 petrol
: Mercedes C-Class
How to diagnose P0205 on a Mercedes-Benz with OBD2
- Read the code and freeze frame with Skanyx and note P0305 (cylinder 5 misfire), P0273 or P0274 (cylinder 5 injector circuit low or high) and any bank 1 or bank 2 lean codes stored with it
- Identify cylinder 5 for your layout. On an inline-five it is the last cylinder, at the gearbox end. On an inline-six it is the second from the back. On a V6 or V8 it depends on the maker: Ford and Audi number one bank first, which puts cylinder 5 on bank 2, while Toyota's 2GR V6 and GM's V8s alternate sides, which puts it on bank 1
- On a longitudinal inline-six the cylinder 5 injector sits towards the bulkhead, where the plug is harder to see. Remove the engine cover and check the connector latch, the pins and the harness branch with a torch rather than by feel
- Measure the injector coil with the ignition off and compare with your engine's specification, then measure again from the ECU pin for injector 5 to include the harness
- Swap injector 5 with a neighbour on the same fuel rail: cylinder 4 on an inline-five, 4 or 6 on an inline-six, or the next cylinder on the same bank on a V engine. If the code moves with the injector, the injector is faulty
- Direct-injection injectors need new PTFE combustion seals whenever they are removed. On common-rail diesels such as BMW's M57 and N57 or Mercedes' OM642, leave removal to a workshop that can recode the injectors afterwards
- If several injector codes are stored together, check the shared supply fuse, relay and grounds before replacing parts
How much does P0205 cost to fix on a Mercedes-Benz? (EUR)
Estimated repair costs for P0205 in EUR, compiled across makes. Expect Mercedes-Benz parts and labour towards the upper end of each range.
| Repair | Parts Cost | Labor Cost | Total Estimate | DIY Difficulty |
|---|---|---|---|---|
| Mend the cylinder 5 connector or wiring (DIY) | €5–€30 | €0–€0 | €5–€30 | Moderate |
| Locate and repair the cylinder 5 wiring fault (shop) | €5–€40 | €60–€180 | €65–€220 | Professional |
| Replace cylinder 5 injector on a petrol engine (shop) | €40–€150 | €60–€160 | €100–€310 | Moderate |
| Replace and code cylinder 5 injector on a common-rail diesel (shop) | €150–€400 | €100–€250 | €250–€650 | Professional |
Prices estimated as of October 2026. Costs vary by region, vehicle, and shop.
Codes related to P0205
These codes are often seen alongside P0205 or point to related issues, on any make:
Looking for the full P0205 reference (all makes, full diagnosis flow, complete repair cost matrix)? See the main P0205 guide