Mercedes-Benz CLA 200 d
Completely new aluminium diesel with NANOSLIDE coating and integrated particulate filter. Noticeably quieter and cleaner than the OM651. Few typical faults known to date.
CLA 200d — Elegant Commuter
110 kW OM654 and DCT in the CLA: stylish, quiet and adequately brisk. A good choice for design-conscious commuters.
Engine Weaknesses 11
Known weak point: the narrow camshaft lobes and rocker arms in the OM654 wear prematurely due to inadequate lubrication. Mercedes issued TSBs.
Symptoms: Ticking or knocking from engine bay, misfires, rough running, engine warning light
Over 800,000 Mercedes diesel vehicles with OM654/OM656 were recalled due to a leaking electric coolant pump. Coolant loss can lead to overheating.
Symptoms: Coolant loss, overheating warning, coolant warning light, engine temperature rises
NOx sensors wear out from soot particles and deliver erroneous readings. Consequence: incorrect AdBlue injection, CEL illumination; if unaddressed, an engine start inhibit may follow. Both sensors can be affected.
Symptoms: CEL, AdBlue warning, fault code P20EE or P204F, message 'No start after X km', rough idle
Early OM654 units had overly soft rocker arms. From engine number 80278367 (10/07/2018) a reinforced version A6540505701 was fitted. Older examples may develop camshaft damage.
Symptoms: Clattering or ticking noise in the valvetrain, poor cold start, increased oil consumption, rough idle
Recall (action code 0591016) affects approximately 10,700 vehicles (built 01/2016–02/2021): individual bolts or chain links wear and can cause chain snap with engine damage.
Symptoms: Rattling on cold start, sudden power loss and engine damage in the event of chain snap, engine warning light
A blocked DPF or coked EGR increases exhaust back pressure. The pressure pushes the turbo shaft axially into the compressor housing, the thrust bearing wears and the turbocharger fails.
Symptoms: Power loss and boost pressure fault, blue smoke from exhaust, whistling from turbocharger, oil leaking from turbo
With predominantly short-trip use the OM654 DPF does not regenerate fully. Leads to oil dilution from stored diesel fuel and premature DPF blockage.
Symptoms: DPF warning light, rising oil level from fuel dilution, power reduction
EGR valve coking up with frequent short-distance use. Clogged passages cause juddering, fault codes and limp mode. Euro 6d exhaust gas recirculation is heavily loaded by design.
Symptoms: Juddering and power loss at part throttle, CEL, increased fuel consumption, rough idle
DPF does not regenerate fully during short-distance driving. Accumulating soot particles lead to warnings, limp mode and, if neglected, filter replacement or engine damage through oil dilution.
Symptoms: DPF warning light, increased fuel consumption, power reduction, engine oil smells of diesel from post-injection
With frequent short-trip driving unburnt fuel enters the engine oil through DPF post-injection. This dilutes the oil, reduces lubrication, and promotes wear in the valve train.
Symptoms: Oil level rising above maximum (oil increase), frequent DPF regeneration cycles, engine warning light, limp mode after aborted regenerations
The OM654 high-pressure injection system operates at up to 2,050 bar. At high mileage or with poor fuel quality, injectors wear and develop quantity errors.
Symptoms: Juddering and knocking, rough idle, starting problems, elevated fuel consumption, in extreme cases cylinder misfires
Vehicle Weaknesses 7
On CLA C118 from the production period August 2019 to July 2020, the turbocharger oil supply line could develop a leak. Oil reached the underbody and the road surface, increased fire risk.
On CLA C118 model year 2020, the voltage supply to the electric power steering assistance could be impaired. In the worst case the steering servo assistance failed while driving.
The 8-speed dual clutch gearbox in the CLA C118 occasionally shows rough gear changes, especially when downshifting and in crawl mode. Software updates help temporarily; clutch packs wear at higher mileages.
The optional Multibeam LED headlights fail or function only partially. Malfunctions affect the adaptive light distribution.
On CLA C118 models with Multibeam LED headlights, occasional malfunctions occur: the high beam assist deactivates unintentionally, or individual LED segments fail.
Starter battery is the most common breakdown cause on the CLA C118. The many assistance and comfort systems place a heavy load on the battery.
A frequent complaint on the CLA C118 and simultaneously the A-Class W177 is clearly audible fuel sloshing in the tank, especially at partial and low fill levels in corners.