KNOWN FAULTS · Mercedes-Benz
Mercedes-Benz Clase A (W177) A 45 S AMG (M139, 2.0) common problems.
2018–2026 · Petrol
Sources are not verified in real time and no entry confirms that your car is affected.
3 known faults with sources
Applies if: Weak points of this model from inspections, breakdown statistics and recalls; anything specific to one engine is stated in the sheet.
Campaigns and weak points of the A-Class W177Known weak points
- Engine / equipment
- Mercedes A-Class W177 (petrol, diesel, plug-in hybrid and AMG)
- Period mentioned
- 2018 onwards
- Symptoms
- On the M282, sometimes higher oil consumption (especially with non-approved oil) and some direct-injection carbon; a front lip that scrapes, a noisy air conditioning and an abrupt lane-change assistant.
- Possible cause described
- Many recalls: eCall sending a wrong position, mis-coded Multibeam headlamps, swarf in the ABS/ESP unit, the rear backrest, brake-fluid loss with the multi-link axle, the brake pedal, airbag mounting, air conditioning with fire risk and too little gearbox oil (possible loss of drive).
- Check for the garage
- Check every campaign by VIN; use Mercedes-approved oil.
- Cost cited in the source
- No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.
Sources from the original database
View full entryApplies if: US bulletin (XENTRY LI46.10-P-078012) for Mercedes-Benz cars with a capacitive steering wheel (code 266) built from 2020; in Europe, ask the dealer.
Assist systems not available messages caused by a steering wheel hands-on detection fault (Mercedes-Benz from 2020)Driver assistance
- Engine / equipment
- Mercedes-Benz with a capacitive steering wheel (code 266)
- Period mentioned
- Built from 2020
- Symptoms
- Messages on the cluster: "Active Emergency Stop Assist not available", "Active Lane Keeping Assist not available" or "Active steering assist not available".
- Possible cause described
- The steering wheel hands-on detection fails: the detection mat, its control unit, the contacts or the wiring. Mercedes-Benz releases new software and SCN coding for the HOSWD control unit (note LI46.10-P-078012).
- Check for the garage
- Ask the garage to apply note LI46.10-P-078012: do not replace the HOSWD control unit, update its software and check the steering wheel contacts, wires and ground connections.
- Cost cited in the source
- No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.
Sources from the original database
View full entryApplies if: US bulletin (XENTRY LI27.19-P-080823) for model years 2021 to 2023 with the 8G-DCT transmission (724.1); in Europe, ask the dealer.
Transmission fault message and shift to neutral from a false overvoltage (8G-DCT of the A-Class, CLA, GLA and GLB 2021–2023)Automatic gearbox
- Engine / equipment
- Mercedes-Benz A-Class (W177), CLA (118), GLA (247) and GLB (247) with the 8G-DCT dual-clutch transmission (724.1)
- Period mentioned
- 2021–2023 (US model years)
- Symptoms
- Transmission fault message, engine warning light on and the gearbox shifts into neutral (N); the fault disappears after switching off and restarting.
- Possible cause described
- The transmission computer alone detects an overvoltage (over 16 V) and stores code P056300, although no other control unit sees it. Mercedes-Benz fixes it with a transmission software update (technical note LI27.19-P-080823).
- Check for the garage
- Ask the workshop to check whether code P056300 was stored with a voltage of 15.75 to 16.5 V and update the transmission software according to note LI27.19-P-080823.
- Cost cited in the source
- No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.