Mercedes-Benz A-Class W177 (2018-2025): known problems and buying guide

Engines and gearboxes

• Petrol M282 1.3 (A 160, A 180, A 200): no guide. Three German sites report higher oil use, and no official Mercedes action was found. Two sites mention carbon deposits from direct injection; one calls them normal.
• A 250 e plug-in hybrid: no source names a hybrid-system fault, so none is listed.
• 7G-DCT dual-clutch gearbox (petrol and K9K): the faults are in the 7G-DCT guide. The gearbox oil recall is in the Recalls table.

In detail

Rear brake fluid loss

The shock absorbers may be too long. The rear brake hoses are under tension and loosen at the caliper, so brake fluid leaks out.

Symptoms: loss of brake fluid. Cars: built March to November 2018 with the multi-link rear axle. Fix: shock absorbers and rear brake hoses replaced, up to four hours in the workshop.

Sources: MB Passion, rear brake recall, CarWiki, A-Klasse problems

Brake pedal can come loose

A manufacturing defect lets the brake pedal come loose sideways. The press says the pedal becomes harder to press, which raises the risk of a crash.

Symptoms: a hard-to-press pedal. Cars: saloon built in 2018 and 2019, as the press report states. gebrauchtwagenberater lists models up to 2019. Fix: the weld is checked and the pedal replaced if needed. Owners are told in writing.

Sources: MB Passion, brake pedal recall, gebrauchtwagenberater, A-Klasse W177 problems, CarWiki, A-Klasse problems

ESP unit with metal particles

Metal particles may sit in the hydraulic unit of the ABS and ESP system, and a check valve may block. The braking distance gets longer. In extreme conditions the pedal travel may also grow.

Symptoms: longer braking distance. Cars: built in April 2018. Fix: ESP unit replaced, about three hours in the workshop.

Sources: MB Passion, ESP recall, CarWiki, A-Klasse problems

Air conditioning drain hose

The condensate drain hose of the air conditioning was routed wrongly. In the worst case several electrical systems fail, or the car will not start.

Cars: built September 2017 to February 2019 (press report). gebrauchtwagenberater gives model year 2019. Fix: hose routing checked and adjusted; workshop time not stated.

Sources: MB Passion, A/C hose recall, gebrauchtwagenberater, A-Klasse W177 problems

7G-DCT gearbox faults

The 7G-DCT guide covers the shift faults, clutch wear, the mechatronic control unit and the auxiliary oil pump. The W177 sources do not separate the 7G-DCT from the 8G-DCT.

For this car, the recalls add a gearbox oil leak (model years 2018-2020, gebrauchtwagenberater) and a low-oil fault that can cut drive (CarWiki). RAC reports a gearbox warning and limp mode on automatic cars.

Sources: gebrauchtwagenberater, A-Klasse W177 problems, CarWiki, A-Klasse problems, RAC Drive, A-Class W177 review

Higher oil use on petrol engines

Some petrol cars burn more oil than normal. Three German sites report it. One says the oil used differs from the maker's approvals; another blames third-party oil. The press advice is oil that meets the maker's approval. No official Mercedes action was found.

Symptoms: higher oil use between services. Cars: petrol M282 (A 160, A 180, A 200).

Sources: gebrauchtwagenberater, A-Klasse W177 problems, AUTO BILD, A-Klasse V 177 used test, CarWiki, A-Klasse problems

Turbocharger oil leak

gebrauchtwagenberater reports a turbo oil feed line problem in model years 2019 and 2020. Auto Express lists leaking turbochargers in a recall without years. Symptom: oil leaking at the turbo. Fix and price not stated.

Sources: gebrauchtwagenberater, A-Klasse W177 problems, Auto Express, used Mercedes A-Class Mk4 review

ISOFIX bracket

The ISOFIX anchorage on the rear seats can fail. No symptom is reported; the risk is a higher chance of injury in a crash. The press report covers the W177 and the CLA (C118), built 30 July to 12 September 2020. gebrauchtwagenberater gives model year 2020.

Fix: the bracket is checked and replaced if needed, 30 to 60 minutes in the workshop.

Sources: MB Passion, ISOFIX recall, gebrauchtwagenberater, A-Klasse W177 problems

Recalls

Rows come from press reports; the KBA (German vehicle authority) database was not read. The UK DVSA checker says "no recalls" for model years 2019 and 2021, but it is a model-year list, not a VIN check.

Check open campaigns by VIN with a Mercedes dealer before you pay.

Maintenance

• Oil: use oil with the maker's approval. Two German sites tie the higher petrol oil use to oil that does not meet it.
• Timing: the A-Class uses timing chains, not belts, according to two press reviews. The sources do not cover the K9K diesel, so check its service book.
• Recalls: keep the workshop papers for the brake, ESP and A/C campaigns.

Sources

English

• Auto Express, used Mercedes A-Class Mk4 review
• RAC Drive, A-Class W177 review
• DVSA recall checker, A-Class 2019

German

• CarWiki, A-Klasse problems
• gebrauchtwagenberater, A-Klasse W177 problems
• AUTO BILD, A-Klasse V 177 used test
• MB Passion, brake pedal recall
• MB Passion, ESP recall
• MB Passion, rear brake fluid recall
• MB Passion, starter wiring recall
• MB Passion, A/C hose recall
• MB Passion, ISOFIX recall

Russian

Seven Russian owner logs (DRIVE2) were read. Each describes one car only, so none is used here.