2010 Mercedes-Benz B-Class petrol: common problems and MOT failures

What goes wrong more than usual on a 2010 Mercedes-Benz B-Class petrol?

Parts flagged at MOT more often on the 2010 Mercedes-Benz B-Class petrol than on all cars registered in 2010.

• Rigid brake pipes2.9× usual
  Mercedes-Benz B-Class

  18.6% All 2010 cars

  6.5%

  Failed outright at MOT: 3.3%, against 1.1% of all 2010 cars. The rest were advisories or minor defects.

  Rough price £100–£400 our estimate

  At the viewing: Ask to see underneath, or check the MOT advisories: corroded brake or fuel pipes get worse every year and fail the MOT when they do.

• Drive shaft (CV) joints3.2× usual
  Mercedes-Benz B-Class

  14.6% All 2010 cars

  4.5%

  Failed outright at MOT: 6%, against 2.2% of all 2010 cars. The rest were advisories or minor defects.

  Rough price £60–£350 our estimate

  At the viewing: Drive slowly on full steering lock in both directions and listen for clicking. Look for split rubber boots behind the front wheels.

• Side repeaters4.9× usual
  Mercedes-Benz B-Class

  6.9% All 2010 cars

  1.4%

  Failed outright at MOT: 5.7%, against 0.9% of all 2010 cars. The rest were advisories or minor defects.

  Rough price £10–£80 our estimate

  At the viewing: Ask a friend to check every light, including brake lights and indicators, while you operate them.

• Individual direction indicators2.3× usual
  Mercedes-Benz B-Class

  7.5% All 2010 cars

  3.2%

  Failed outright at MOT: 3.4%, against 1.3% of all 2010 cars. The rest were advisories or minor defects.

  Rough price £10–£80 our estimate

  At the viewing: Ask a friend to check every light while you work the switches: indicators, brake lights, fog lights and reversing lights.

• Link ball joint covers2.4× usual
  Mercedes-Benz B-Class

  6.3% All 2010 cars

  2.6%

  Failed outright at MOT: 3.2%, against 1.5% of all 2010 cars. The rest were advisories or minor defects.

  Rough price £60–£150 (one joint) ClickMechanic

  At the viewing: Listen for knocking over bumps and check the rubber boots behind the wheels aren't split.

Common 2010 Mercedes-Benz B-Class petrol MOT failures and advisories

The share of 2010 Mercedes-Benz B-Class petrol MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

• Brakes
  37% of testsRough price £150–£350

  At the viewing: Look for a lip on the disc edges and feel for judder or pulling when braking firmly from about 40mph.

• Tyres
  31% of testsRough price £70–£150

  At the viewing: Check the tread on all four tyres, including the inside edges, and look for cracks or bulges.

• Suspension
  29% of testsRough price £120–£400

  At the viewing: Listen for knocks over speed bumps, and look behind each front wheel for a snapped coil spring.

• Lights and electrics
  28% of testsRough price £10–£80

  At the viewing: Ask a friend to check every light, including brake lights and indicators, while you operate them.

• Driveshafts and joints
  15% of testsRough price £60–£350

  At the viewing: On full steering lock, drive slowly and listen for clicking from the front wheels.

• Wipers, windscreen and mirrors
  10% of testsRough price £15–£250

  At the viewing: Check for chips in the driver's view, and test the wipers and washers.

Questions to ask the seller before buying a 2010 Mercedes-Benz B-Class petrol

Ask before you travel to see it. A seller who knows the car will have answers, and receipts.

1. Any recent work on the rigid brake pipes? (Flagged at MOT 2.9× as often on the 2010 Mercedes-Benz B-Class petrol as on other cars the same age.)
2. Any recent work on the drive shaft (cv) joints? (Flagged at MOT 3.2× as often on the 2010 Mercedes-Benz B-Class petrol as on other cars the same age.)
3. Any recent work on the side repeaters? (Flagged at MOT 4.9× as often on the 2010 Mercedes-Benz B-Class petrol as on other cars the same age.)
4. Can I see the service history and receipts for any big jobs?