2019 Mercedes-Benz B-Class Problems: 4 Known Issues

On the 2013-2019 Mercedes-Benz B-Class, on certain vehicles, the power steering control unit may corrode, letting moisture in so that it fails. That could cause a loss of power steering assist and a sudden increase in steering effort, especially at low speed, increasing the risk of a crash. Applies to: Certain 2013-2019 model-year B-Class (W246) sold in Canada (B 250) that were originally sold or ever registered in areas of heavy road salt use (Ontario, Quebec, New Brunswick, Nova Scotia, Prince Edward Island and Newfoundland & Labrador), per Transport Canada recall 2020-617 (Mercedes-Benz 4694202) and its expansion 2021-507 (Mercedes-Benz 4694203); CLA and GLA are also listed. Only a Mercedes-Benz dealer can confirm whether a specific VIN is included.

On the 2012-2019 Mercedes-Benz B-Class, owners of W246 B-Class cars with the 7G-DCT dual-clutch automatic describe a pause of about a second before the clutch bites when pulling away, and jerking or harsh shifts at low speed. One owner of a high-mileage 2014 B 220 CDI reports judder that a transmission reset did not cure; the cause was not diagnosed in the thread. Applies to: Second-generation (W246) B-Class with the 7G-DCT automatic: model years 2012-2018 in Europe and 2013-2019 in Canada (B 250), with the M270 petrol (1.6 and 2.0 litre, including the B 200 Natural Gas Drive), OM651 diesel or OM607 1.5-litre diesel. The owner reports linked here are from a B 200, a B 200 CDI and a 2014 B 220 CDI. Not the B250e electric (W242), which has a single-speed drive unit, and not manual-gearbox cars. Mileage when it happened, as stated in the linked owner reports: 3,200 km (about 2,000 miles), 110,000 km (about 68,400 miles) on a 2016 and 230,000 km (about 142,900 miles) on a 2014.

On the 2012-2019 Mercedes-Benz B-Class, w246 owners report a parking-brake malfunction warning, and in one case the electric parking brake worked on one side only. One owner found water in the left rear actuator motor and replaced both actuators, but the warning stayed until the parking-brake control module connectors inside the right rear of the car were unplugged and reseated. Applies to: Second-generation (W246) B-Class with the electric parking brake: model years 2012-2018 in Europe and 2013-2019 in Canada (B 250). The owner reports linked here include a 2012 car. Owners report the rear actuator motors, the wiring and the control module as the parts involved; the cause on a given car must be diagnosed.

On the 2012-2019 Mercedes-Benz B-Class, owners of W246 B-Class cars with the M270 petrol engine report coolant warning messages, an engine warning light with the temperature stuck around 70-80 C, or the gauge swinging, with dealers replacing an electronically controlled thermostat that stuck open. Some gauge movement is normal on this engine, and owners report a dealer engine-software update that steadied it where no hardware fault was stored. A thermostat replacement did not always cure it: other causes found were a crack elsewhere in the cooling system and a stuck valve in the water pump. Applies to: Second-generation (W246) B-Class with the M270 petrol engine (B 180, B 200, B 220 4MATIC, B 250): model years 2012-2018 in Europe and 2013-2019 in Canada (B 250). The owner reports linked here are from a B 220 4MATIC, a 2012 B 200 and other W246 petrol cars. Not the diesel or electric models. Mileage when it happened, as stated in the linked owner reports: 65,000 km (about 40,400 miles) on a 2013, 74,000 km (about 46,000 miles) on a 2012, 142,000 km (about 88,200 miles) on a 2012 and 176,000 km (about 109,400 miles) on a 2012.