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Mercedes-Benz C-Class C 300 de Business Solution common faults.

2021–, saloon, diesel, 197 HP.

The fault list covers: M139E20DEHLA, OM654M engine, MB7250 transmission.

What you save stays on this device only. My saves

2 fault write-ups. Both are important. 14 recalls.

If you know the year, pick it. Faults for other years drop out of the list.

Before you buy

Known faults

2 important faults

critical1

OM654 / OM656: vacuum controlled coolant pump leak, fire risk

critical

On the OM654 and OM656 diesels the maker started a recall over the vacuum controlled coolant pump (maker action code: 2090008). The fault: a leak can develop between the coolant and the vacuum circuit; if coolant reaches the electric switching valves, an electrochemical reaction can raise the temperature of the part, and a fire risk cannot be ruled out.

Show the rest

The fix: replacing the electric switching valve and a software update. The campaign started at the end of 2021; the affected group is the C-Class, E-Class and other OM654/OM656 models.

A recall on the model does not mean it was carried out on this car. Only the franchised dealer can tell you, by VIN.

What to check

  • Ask the franchised dealer by VIN: is action 2090008 OPEN or CLOSED
  • Check the coolant level and look around the vacuum system for leaks
  • Ask for the service sheet: a switching valve replacement plus a software update is part of the campaign
1 more steps in the write-up

expensive1

OM654 / OM656 diesel: roller finger follower wear and DPF driven oil dilution

expensive

The modern OM654 four cylinder diesel (and the modular OM656 six cylinder) carries two weaknesses on the used market that reinforce each other.

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1) Roller finger followers (Rollenschlepphebel). According to the German technical press, on some cars the followers wear early at around 100,000 to 120,000 km. On 10 July 2018 the maker introduced a strengthened follower from engine number 80278367 (new part number A6540505701 in place of the old A6540501100). On early built cars the risk is higher. A faulty follower develops so much heat that the removed metal shows blue discolouration (Anlaufspur).

2) Oil dilution. The post injection needed to regenerate the particulate filter puts diesel fuel into the engine oil. With short urban use the engine does not get warm enough, the fuel does not evaporate, the oil thins out, and the follower and valvetrain are exactly what suffers most from poor lubrication.

The timing chain sits on the gearbox side: if it stretches, the replacement is labour intensive. There are few complaints of a broken chain, but on the early series about 5,000 cars were recalled for a weak chain, and the Tritan 15 coating was changed to Tritan 18.

between 80,000 and 160,000 km

What to check

  • Listen to the engine on a cold start: metallic ticking or rattling from the follower or the chain is suspect
  • Ask for the engine number: cars below 80278367 (before July 2018) are the old follower group
  • Check the service book: how often and with what oil (MB 229.52 is recommended) it was changed. Long intervals plus urban use is the worst pairing
2 more steps in the write-up

Checklist

Mercedes-Benz C-Class C 300 de Business Solution

First what you would check on any car. Then the faults of this model.

Before you buy

Checklist

The printed sheet starts with what you would check on any car. What you tick stays on this device only.

On every car

Ask the owner

Faults of this model

vinkodex.com · Before you buy it, see what can go wrong.

Official recall14 recallsShow

The manufacturer fixes these for free at a franchised dealer. Ask with the VIN whether it was done.

Most recent: 18 May 2026

SR/01626/26Safety recallInjuries18 May 2026 · EU Safety Gate

The wheel bolts were not tightened in accordance with the torque specifications. The bolts and the wheel assembly could detach while the vehicle is in motion, increasing the risk of accidents. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: 18/05/2026

The authority's notice

23V462000ELECTRICAL SYSTEM:WIRINGELECTRICAL SYSTEM:WIRING30 June 2023 · NHTSA (USA)

Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2022-2023 C300 and 2023 AMG C43 vehicles. The transmission wiring harness may be the incorrect length, which can result in harness damage and a loss of drive power.

Risk: A loss of drive power can increase the risk of a crash.

Remedy: Dealers will inspect and repair the transmission wiring harness routing, as necessary, free of charge. Owner notification letters were mailed August 18, 2023. Owners may contact MBUSA customer service at 1-800-367-6373. MBUSA's number for this recall is 2023070015.

The authority's notice

A12/00196/24Safety recallFireno date · EU Safety Gate

A bolt on the high-pressure pump may be faulty, which could impair the sealing function between the high-pressure pump and the tandem oil pump. As a result, oil and fuel may leak onto the road, posing a risk to the following traffic. In addition, oil and fuel could come into contact with hot engine parts, increasing the risk of fire. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

A12/00410/24Safety recallFire, Injuriesno date · EU Safety Gate

Due to a faulty fixation, the rear axle wiring harness may be damaged. This may cause sudden momentum loss, increasing the risk of an accident. In addition, electrical current may cause an increased temperature in the damaged area, creating a risk of fire. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

A12/00681/24Safety recallFireno date · EU Safety Gate

The tank strap may not have been screwed on with the required torque, causing the screw to loosen and the fuel tank to drop, possibly hitting the drive shaft. This could damage the tank and cause fuel leaks, increasing the risk of fire. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

A12/00766/24Safety recallFireno date · EU Safety Gate

The bolts on the terminal clamps of the starter battery may come loose. This could increase the electrical contact resistance, leading to a local temperature increase at the terminal clamp connection point. This creates a risk of fire. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

A12/00939/24Safety recallFire, Injuriesno date · EU Safety Gate

A fuse may be faulty, which can lead to engine failure or impairment of the restraint functions and instrument cluster. This increases the risk of an accident, injuries and fire. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

A12/01679/23Safety recallInjuriesno date · EU Safety Gate

Polluted brake fluid could lead to increased wear of the braking system and a reduced braking performance. This could also impair the functioning of the electronic stability program (ESP), creating a risk of an accident. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

A12/01767/23Safety recallFireno date · EU Safety Gate

The tightening torque on the screw connections on certain 12V and 48V ground points may be insufficient. This may lead to improper wiring fixation, which may cause rise of temperature in this area, increasing the risk of fire. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

A12/02964/23Safety recallInjuriesno date · EU Safety Gate

The windows may not be properly attached and can fall out, creating a risk of an accident. The front airbag may not work as intended if the windscreen comes loose, increasing the risk of injury. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

SR/00633/25Safety recallFireno date · EU Safety Gate

Ground-cable bolts may not have been tightened with sufficient torque. This can lead the wiring harness not to be properly secured and result in an increase of the connection's electrical resistance. The temperature can rise in this area, increasing the risk of fire. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

SR/01846/25Safety recallInjuriesno date · EU Safety Gate

The safety cap on the end mount of the seat belt of the passenger seat may not be correctly installed. The safety cap could become detached over the life of the vehicle, and the belt would no longer be fixed in its anchorage. In the event of abrupt deceleration or in the event of an accident, the belt may no longer have a restraining effect, thereby increasing the risk of accident/injury. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

SR/02431/25Safety recallFire, Injuriesno date · EU Safety Gate

An improperly reworked fuse box may lead to breaks in contact or incorrect fuse ratings. Therefore, systems connected to the fuse could fail, including the vehicle losing drive without warning as well as the restraint systems or the instrument cluster being compromised. This could lead to injury or fire. The product does not comply with the requirements laid down in the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

SR/03352/25Safety recallInjuriesno date · EU Safety Gate

A manufacturing defect in the steering coupling may lead to loosen mechanical connection between the steering wheel and the steering box, leading to a loss of steering and increasing the risk of an accident. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

The authority's notice

Engine and transmission

2 engines · 1 transmissions

M139E20DEHLA

10–350 kW (14–476 HP) · petrol

MB7250 · 9G-Tronic, longitudinal (Mercedes 725.0 / NAG3)

automatic · 9 speed

Torque limit700 Nm
MakerMercedes-Benz

We built the code from the model and the gear count. The factory sheet does not state it. More than one engine code is possible. The fault list shows the faults of each.

Variant data

What is in this version

Factory data

Trim
C 300 de Business Solution
Body
saloon
Fuel
diesel
Transmission
automatic
Engine size
1993 cc
Power
145 kW (197 HP)
Drive
RWD
Production
2021–

Factory service interval

The manufacturer specifies this for this version. Of the mileage and the time, the one that comes first is the one that counts.

  • Air filter

    • 60,000 km or 4 years

  • Cabin (pollen) filter

    • 30,000 km or 2 years

  • Brake fluid change

    • first: 3 years, then 2 years(first change at 3 years, then every two years)

  • Spark plugs, petrol

    • 60,000 km or 6 years
All W206 versions

Information, not an expert opinion

We write the descriptions, and we put the source next to them. A person reviews them before they go out. They are still information, not a technical expert opinion.

  • A fault on the list does not mean the car you are looking at has it.
  • A fault missing from the list does not mean the model is fault-free. Write-ups are made model by model. Not all of them are done.
  • You decide whether to buy. This is no substitute for an inspection. That needs a workshop and a history check.
Details in the terms