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2014 Mercedes-Benz B-Class problems, recalls and owner complaints
What the 2014 Mercedes-Benz B-Class has been recalled for, how often it fails the UK MOT and what owners report, from official government data. Updated October 25, 2026.
- 0safety recalls
- 21owner complaints
- 0crash reports
- 0fire reports
- 25%fail the UK MOT
21 complaints, against an average of 19 for the other 3 Mercedes-Benz B-Class model years.
Every Mercedes-Benz B-Class model year with its number of owner complaints. Pick a year to compare.
What goes wrong with the 2014 Mercedes-Benz B-Class?
The components named most often in the 21 owner complaints. One complaint can name several, so the shares can add up to more than 100%.
What symptoms do 2014 Mercedes-Benz B-Class owners describe?
Found by reading the text of all 21 owner complaints. Tap a symptom for the answer, a real owner quote and any related recall.
Has the 2014 Mercedes-Benz B-Class been recalled?
NHTSA lists no safety recalls for the 2014 Mercedes-Benz B-Class as of October 25, 2026. Recalls can be issued at any time, so check your VIN before you rely on this.
Is the 2014 Mercedes-Benz B-Class recalled in the UK or Europe?
Recalls issued by the UK's DVSA and through the EU's Safety Gate system that cover this model and build period. European models can differ from U.S. ones, and "years estimated" means the recall gave no build dates, so confirm your own car with your registration or VIN.
UK DVSAUpdate to the diesel engine control unit software to improve the emissions
Risk: As a result of a directive from Germany's Federal Motor Transport Authority (KBA) changes are required to certain specific calibration functions within the engine management systems of certain vehicles.
Fix: Conduct an update to the diesel engine control unit software.
UK DVSAThe refrigerant in the air conditioning system does not meet legal requirements
Risk: The refrigerant used in the air conditioning system does not meet legal requirements.
Fix: The air conditioning system will be adapted for the usage of the new refrigerant.
UK DVSAThe refrigerant used in the air condition system does not meet legal requirements
Risk: The refrigerant used in the air conditioning system does not meet legal requirements.
Fix: Adapt the air conditioning system for usage of the new refrigerant.
UK DVSAThe refrigerant used in the air conditioning system may not meet legal requirements
Risk: The refrigerant used in the air conditioning system does not meet legal requirements
Fix: The air conditioning system will be adapted for the usage of the new refrigerant.
UK DVSAAir condition system refridgerant does not meet requirements
Risk: The refrigerant used in the air condition system does not meet legal requirements.
Fix: The air conditioning system to be adapted for the usage of the new refrigerant (R1234yf).
UK DVSAElectrical wiring in steering assembly may be insufficiently grounded
Risk: The steering column clock spring may break. This will cause warning messages to illuminate in the instrument cluster but in extreme instances it may cause the driver's airbag to deploy.
Fix: Affected vehicles will be recalled to establish sufficient grounding of the steering components
UK DVSASteering components may be insufficiently grounded
Risk: It has been determined that the steering airbag electrical components are insufficiently grounded. Failure of the steering column module clock spring could result in an inadvertent deployment of the driver airbag which may cause risk of injury to the driver and an increased risk of a potential collision.
Fix: On affected vehicles the manufacturer will fit a contact bridge to the outer race of the steering column top bearing which will provide correct grounding.
UK DVSAElectrical wiring in steering assembly may be insufficiently grounded
Risk: The steering column clock spring may break. This will cause warning messages to illuminate in the instrument cluster but in extreme instances it may cause the driver's airbag to deploy.
Fix: Affected vehicles will be recalled to establish sufficient grounding of the steering components.
UK DVSAElectrical wiring in steering assembly may be insufficiently grounded
Risk: The steering column clock spring may break. This will cause warning messages to illuminate in the instrument cluster but in extreme instances it may cause the driver's airbag to deploy.
Fix: Affected vehicles will be recalled to establish sufficient grounding of the steering components.
UK DVSAStarting current limiter may overload
Risk: Where the car incurs severe engine damage resulting in the engine failing to turn over (engine seizure) and if the driver repeatedly attempts to start the engine despite the engine not cranking the very high electrical current could lead to overheating of the starting current limiter and the potential for a fire.
Fix: Recall the vehicles that are likely to be affected and install an additional fuse in the electrical line to the starter.
UK DVSARisk of fireYears estimated
Risk: A threaded connection in the Prefuse box may not be tightened to the correct specification. This may excessive resistance and create a heat source. This could cause a fire. Additionally vibration may cause power disruption which could affect the operation of steering power assistance ABS SRS and/or instrument failure..
Fix: On affected vehicles check threaded connection and where necessary replace fuse box.
UK DVSARear bench seat may lift up from the rear in a collision & attached seat belts may not be anchored correctly
Risk: On 'B' Class models fitted with 'Easy Vario' rear seat option a bolt securing the seat bench to the body may have been omitted during production. This may allow the seat bench to lift during a frontal collision. Seat belt effectiveness may also be compromised.
Fix: On affected vehicles check for presence and tightness of retaining screws. Fit new screws where necessary and tighten all screws to specification.
UK DVSAVehicle may cut out
Risk: In rare cases the propulsion control unit may send an incorrect message. This may cause the electric power train to shut down. Power can be restored by the normal start sequence.
Fix: Update software on affected vehicles.
UK DVSAFront passenger airbag may not deploy
Risk: Certain fuses in the passenger's footwell may not have been fitted correctly. This may adversely affect the instrument cluster windscreen wipers and the passenger seat occupancy recognition system. In certain conditions this may cause the passenger's air bag not to deploy in an accident.
Fix: On affected vehicles check fuses and if necessary replace fuse box.
UK DVSAOil may leak
Risk: On certain diesel engines the 'O' ring may not have been produced to the correct specification. This may allow oil to leak and contaminate the environment. If excessive oil is lost engine damage may occur.
Fix: On affected vehicles replace the chain tensioner sealing ring.
EU Safety GateThe occupant classification system for the front passenger seat may not be calibrated in accordance with the specifications.Consequently, an installed child seat may be identified as a person or a small, light person as a child seat. As a result, the passenger airbag could be activated despite the presence of a child seat or the passenger airbag could fail to activate despite the presence of a person on the passenger seat, increasing the risk of injuries.
Measures: 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
EU Safety GateThe steering column is not sufficiently earthed.As a result, in the event of an electrostatic discharge, the driver's airbag may be triggered when not required. This could cause an accident.
Measures: 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
EU Safety GateThe starter current limiter may be overloaded and overheat.As a consequence, the surrounding components could ignite, leading to a fire.
Measures: 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: 01/09/2017
EU Safety GateThe back screws on the rear seats could be missing on one side.Passengers would therefore not be protected from unsecured luggage in the event of a frontal collision, because the rear seat could be lifted from behind. Furthermore, the required seat belt anchorage may not be guaranteed.
Measures: 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
EU Safety GateIncorrect software was installed in the Electronic Stability Programme (ESP) control device of the vehicles affected.
Measures: 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
EU Safety GateOwing to the incorrect installation of fuses, various vehicle functions might fail.These include the passenger presence detector for the passenger seat, the status display for the passenger airbag, the instrument cluster and the windscreen wipers. This could lead to an accident or an increased risk of injury for the passenger in the event of an accident.
Measures: Type of economic operator taking notified measure(s): Other; Category of measure(s): Recall of the product from end users; Date of entry into force: Unknown
EU Safety GateThe gasket seal for the engine's chain tensioner may display incorrect settling behaviour.Over time, this may result in the chain tensioner detaching from the threaded hole on the cylinder head and the leakage of engine oil. The loss of large amounts of engine oil may contaminate the road, leading to a possible hazard for traffic following behind.
Measures: Type of economic operator taking notified measure(s): Other; Category of measure(s): Recall of the product from end users; Date of entry into force: Unknown
EU Safety GateThe seat belt anchorage is not adequately fixed, which may cause injuries to passengers in the event of an accident or sudden brake.
Measures: Type of economic operator taking notified measure(s): Other; Category of measure(s): Recall of the product from end users; Date of entry into force: Unknown
How often does the 2014 Mercedes-Benz B-Class fail its MOT?
Why they failed: the share of failed tests with at least one fault in each area (a test can fail on several). Cars first registered in 2014, tested in Great Britain in 2023; first registration is usually, but not always, the model year. Source: DVSA anonymised MOT tests and results, Open Government Licence v3.0.
What do 2014 Mercedes-Benz B-Class owners report?
12 of the 21 complaints, the most recent for the most-reported components, as the owners wrote them. NHTSA removes names and VINs; long reports are trimmed. CarHooq has not verified individual claims.
The contact owns a 2014 Mercedes-Benz B-Class Electric Drive. The contact stated that after stopping at a stop sign, the vehicle lost motive power before the "Malfunction visit workshop" and "Stop switch engine off" messages were displayed. After restarting the vehicle, the vehicle returned to normal functionality; however, the failure recurred more frequently. No warning lights were illuminated. The vehicle was towed to the dealer and diagnosed with an electric drive motor failure. The contact was informed that the electric drive motor needed to be replaced. The vehicle was not repaired. The…
Coolant leak causing catastrophic drive unit failure.
Motor suddenly stopped on highway. This was extremely dangerous. Vehicle transported to Mercedes Benz, they have indicated the electric drive motor has failed. This is the second drive motor in this car that has failed in only 48K miles. We have two of these cars, same year and model. The motor has also failed in the other vehicle. There is an entire Facebook group talking about failures of the drive units in these cars. PLEASE FORCE MERCEDES TO DO SOMETHING!
TL* THE CONTACT OWNS A 2014 MERCEDES BENZ B250E. THE CONTACT STATED THAT WHILE DRIVING AT APPROXIMATELY 30 MPH, THE BATTERY LIGHT FLASHED AS THE VEHICLE BEGAN TO LOSE POWER. DESPITE THE FAILURE, THE CONTACT WAS ABLE TO COAST THE VEHICLE TO HER HOME. THE NEXT DAY, MULTIPLE ATTEMPTS WERE MADE TO START THE VEHICLE AS SEVERAL WARNING LIGHTS APPEARED ON THE INSTRUMENT PANEL. DUE TO THE FAILURE, THE CONTACT HAD THE VEHICLE TOWED TO MERCEDES-BENZ OF ONTARIO (3787 E GUASTI RD, ONTARIO, CA 91761) WHERE THEY DIAGNOSED THE VEHICLE WITH A DEFECTIVE DRIVE ELECTRIC MOTOR INTERNAL FAULT AS WELL AS A…
TL* THE CONTACT OWN A 2014 MERCEDES BENZ B-CLASS ELECTRIC. THE CONTACT STATED WHILE HIS WIFE WAS DRIVING 55 MPH, AN UNKNOWN YELLOW WARNING LIGHT ILLUMINATED INDICATING ASSISTANCE REQUIRED. THE DRIVER CONTINUED TO DRIVE THE VEHICLE AND SHORTLY AFTER, WHILE ATTEMPTING TO PARK ON THE SIDE OF THE ROAD, ANOTHER RED WARNING LIGHT WAS ILLUMINATED AND THE VEHICLE STALLED. THE VEHICLE WAS NOT DRIVABLE. THE VEHICLE WAS TOWED TO THE LOCAL DEALER MERCEDES-BENZ OF ALEXANDRIA (200 S PICKETT ST, ALEXANDRIA, VA 22304, (703) 341-2100) WHERE IT WAS DIAGNOSED WITH NEEDING THE DRIVETRAIN TO BE REPLACED. THE…
THIS IS AN ELECTRIC VEHICLE. IN NORMAL OPERATION, WHEN THE CAR IS SLOWING, AND ALMOST AT A STOP, IT COMES OUT OF REGENERATIVE BRAKING MODE, AND ENTERS THRUST MODE, SO THAT IF THE BRAKE IS RELEASED WHEN STOPPED, THE CAR WILL BEGIN TO ROLL. IN THIS VEHICLE, SOMETIMES THE CAR EXITS REGENERATIVE BRAKING MODE AND ENTERS THRUST MODE WHEN SLOWING AT HIGH SPEED, SUCH AS WHEN EXITING A HIGHWAY RAMP. THIS IS EXTREMELY DANGEROUS, AS BRAKING IS MOMENTARILY AND UNEXPECTEDLY LOST WHEN IT IS NEEDED MOST. I TOOK THE CAR INTO THE DEALERSHIP, AND THEY WERE UNABLE TO FIND ANY ISSUES OR FAULT CODES. AS THE ISSUE…
WHEN ATTEMPTING TO REVERSE OUT OF PARKING STALL VEHICLE WOULD NOT MOVE, ALMOST AS IF EMERGENCY BRAKE WAS BEING APPLIED EVEN THOUGH EBRAKE WAS OFF. TURNING ON AND OFF IGNITION DID NOTHING. REPLACE 12 V BATTERY DID NOTHING. WARRANTY WORK ON CONTROL UNIT PERFORMED MULTIPLE TIMES IN 2017/2018/2019 EVEN THOUGH THE SOFTWARE 'FIXED' THE ISSUE RELATED TO THE RECALL NHTSA CAMPAIGN ID: 15V655000 IN 2015. DEALER STATES MUST REPLACE ENTIRE POWER TRAIN AT A COST OF $11,500. VEHICLE HAS 72K MILES AND LOAN BALANCE IS OVER $12K. THE POWER TRAIN PROVIDED BY TESLA WAS REPLACED IN TESLA'S OWN VEHICLES AS WELL AS…
VEHICLE BATTERY WARNING LIGHT CAME ON INSTRUCTING TO STOP DRIVING VEHICLE IMMEDIATELY. LIKE SO MANY OTHER OWNERS WHO HAVE FILED COMPLAINTS, MERCEDES DEALER-MECHANIC SAID THAT COOLANT HAD GOTTEN INTO BATTERY AND DRIVE UNIT NEEDS TO BE REPLACED. ESTIMATED COST $12,000 - RENDERING CAR TOTALLED. INDEPENDENT EV SPECIALIST HAS PRESSURE TESTED COOLING SYSTEM AND FINDS NO LEAKS. FORTUNATELY, I WAS IN A SAFE PLACE AT THE TIME I NEEDED TO STOP THE CAR. IF I HAD BEEN OUT ON THE FREEWAY DURING HEAVY TRAFFIC OR AT NIGHT, THIS WOULD HAVE BEEN UNSAFE. IF THERE ARE PROBLEMS WITH THE COOLANT AND DRIVE UNIT, IT…
THE "MALFUNCTION" LIGHT APPEARED AND VEHICLE LOST POWER IMMEDIATELY. AFTER COMING TO A COMPLETE STOP, THEN SWITCHING THE IGNITION OFF AND BACK ON AGAIN, THE CAR OPERATED NORMALLY AND THE "MALFUNCTION" LIGHT DISAPPEARS. THIS OCCURRED THREE TIMES: DURING HIGHWAY DRIVING (55 MPH), ON A COUNTRY ROAD (45 MPH), AND AT ALMOST A STOP (5 MPH). ONE OCCURRENCE WAS IN THE EARLY EVENING ON A HOT DAY AND TWO WERE EARLY IN THE MORNING WHEN TEMPERATURES WERE COOL. TWO OF THESE FAILURES WERE VERY DANGEROUS CIRCUMSTANCES AND IT IS VERY LUCKY THAT NO ONE WAS NEARBY ON THE ROAD AT THAT TIME. SINCE IT IS A FULLY…
THIS IS AN ELECTRIC VEHICLE. WHEN SLOWING DOWN THE PADDLE SHIFTERS CAN BE USED TO PUT THE CAR IN 'D-' MODE, FOR MORE AGGRESSIVE ENGINE BRAKING. THIS INCREASES THE RATE OF DECL WITHOUT USING THE MECHANICAL BRAKES. THIS HAS WORKED WELL FOR FOUR YEARS AND 65,000 MILES. TODAY THERE WAS A 'ONE TIME' MALFUNCTION. I DID THE USUAL 'D-' 'DOWN SHIFT' TO SLOWDOWN FROM 30 MPH, IN TRAFFIC, FOR RED LIGHT. THE CAR DID NOT AGGRESSIVELY SLOW DOWN AND I APPLIED THE BRAKES. I NOTICED THE CAR NEED EXCESSIVE BREAK PEDAL PRESSURE TO MAKE WHAT SHOULD BE A NORMAL STOP. I GLANCED DOWN AT THE POWER METER AND IT IS…
EXTREMELY DANGEROUS SUDDEN LOSS OF POWER WHILE DRIVING 70+ MPH ON BUSY HIGHWAY. WAS ALMOST INVOLVED IN A SERIOUS TRAFFIC COLLISION BECAUSE IT A STOPPED IN THE ROAD. ATTEMPTS TO RESTART THE VEHICLE FAILED. COULD NOT GET THE VEHICLE OUT OF "PARK" AND WAS UNABLE TO SWITCH IT INTO "NEUTRAL" TO ROLL THE VEHICLE OUT OF THE LANE OF HIGH SPEED TRAFFIC. THE INABILITY TO GET THE VEHICLE INTO "NEUTRAL" FURTHER COMPROMISED MY SAFETY AND THE SAFETY OF OTHER DRIVERS ON THE HIGHWAY. MAIN LOW VOLTAGE 12V BATTERY DIED SOON AFTER INCIDENT AND CREATED AN ISSUE FOR TOW TRUCK OPERATOR. HE HAD A LOT OF TROUBLE…
BEGINNING AT ABOUT 4500 MILES WE BROUGHT THE CAR IN TO THE SHOP AFTER COMING TO A STOP; WE CALL IT THE 'CLOMP!' IT WILL UNEXPECTEDLY ROCK FORWARD CREATING A VERY UNSAFE FEELING. THEN THE FOLLOWING MONTH, THE 'CLOMPING' PRESENTED ITSELF AGAIN SO MY WIFE RETURNED THE VEHICLE TO THE DEALERSHIP TO DEMONSTRATE. A FEW WEEKS LATER, THE CAR BEGAN MAKING A LOUD TURBINE NOISE, AND THE ROCKING FORWARD AFTER COMING TO A STOP RE-PRESENTED ITSELF AGAIN SO WE RETURNED THE CAR TO SERVICE. THEN THE FOLLOWING MONTH THE CAR CONTINUED TO RANDOMLY LUNGE FORWARD AFTER COMING TO A STOP, MY WIFE CALLED THE SERVICE…
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2014 Mercedes-Benz B-Class: questions owners ask
Is the 2014 Mercedes-Benz B-Class reliable?
NHTSA data alone cannot rate reliability, but it shows what owners reported. Owners filed 21 complaints with NHTSA about the 2014 Mercedes-Benz B-Class; the most common categories were power train (10, 47.6%), electrical system (8, 38.1%), engine (6, 28.6%). There are no safety recalls listed for this model year.
What are the most common problems with the 2014 Mercedes-Benz B-Class?
Across 21 owner complaints filed with NHTSA, the categories mentioned most often are power train (47.6% of complaints), electrical system (38.1% of complaints), engine (28.6% of complaints), service brakes (14.3% of complaints), fuel/propulsion system (9.5% of complaints). One complaint can name several components.
Does the 2014 Mercedes-Benz B-Class have any recalls?
As of October 2026, NHTSA lists no safety recalls for the 2014 Mercedes-Benz B-Class. Recalls can be issued at any time, so check your VIN at nhtsa.gov/recalls.
Why does my 2014 Mercedes-Benz B-Class stall, lose power or shut off while driving?
8 of the 21 owner complaints NHTSA has on file for the 2014 Mercedes-Benz B-Class (38.1%) describe the engine stalling, losing power or shutting off while driving. One owner wrote: "When attempting to reverse out of parking stall vehicle would not move, almost as if emergency brake was being applied even though ebrake was off. turning on and off ignition did nothing. replace 12 v battery did nothing." (NHTSA complaint 11287815, December 2019). If it happens to your car, check your VIN for open recalls at nhtsa.gov/recalls and report the problem to NHTSA; complaints are what trigger investigations.
Why does the battery keep dying on my 2014 Mercedes-Benz B-Class?
3 of the 21 owner complaints NHTSA has on file for the 2014 Mercedes-Benz B-Class (14.3%) describe a dead or draining battery. One owner wrote: "When attempting to reverse out of parking stall vehicle would not move, almost as if emergency brake was being applied even though ebrake was off. turning on and off ignition did nothing. replace 12 v battery did nothing." (NHTSA complaint 11287815, December 2019). If it happens to your car, check your VIN for open recalls at nhtsa.gov/recalls and report the problem to NHTSA; complaints are what trigger investigations.
Check your own B-Class
Counts are a starting point, not a verdict: popular models collect more complaints because more of them are on the road, and NHTSA does not verify individual reports. To see whether a recall is still open on your car, enter your VIN at nhtsa.gov/recalls (U.S.) or your registration at check-vehicle-recalls.service.gov.uk (UK). Had a safety problem? Report it to NHTSA; complaints are what trigger investigations and recalls.
Data: NHTSA Office of Defects Investigation recall and complaint databases (public domain), DVSA anonymised MOT results (Open Government Licence v3.0), DVSA vehicle recalls (Open Government Licence v3.0), EU Safety Gate alerts (© European Union), retrieved October 25, 2026. Model year 2014 only.