2019–2025 Mercedes-Benz CLA · common problems & known faults

Dual clutch judder and hesitation from standstill

Typically appears

60,000+ miles

What to inspect

Pull away repeatedly from cold in traffic

MBUX screen freezes and reboot loops

Typically appears

Age-related

What to inspect

Cycle navigation, audio and voice control

Front bush wear and knocking on lowered AMG Line cars

Typically appears

50,000+ miles

What to inspect

Drive over speed humps and listen at the front

Kerbed alloys and scuffed front splitter

Typically appears

Age-related

What to inspect

Inspect all four wheels and the front lip

Oil seepage down the front of the engine block from the timing chain cover.

Typically appears

30,000-50,000 miles

What to inspect

Shine a torch down the right side of the engine bay past the alternator to check for fresh oil misting or weeping on the block.

Frameless door windows failing to drop correctly upon opening, causing seal damage and wind noise.

Typically appears

20,000-40,000 miles

What to inspect

Open and close both front doors rapidly three times. Ensure the glass drops a few millimetres instantly and seals tightly under the rubber lip upon closing.

Heavy condensation or water pooling inside the rear LED tail light clusters.

Typically appears

3-5 years

What to inspect

Check the lower edges of the boot-mounted tail lights for visible water droplets or green algae build-up. Switch on the hazard lights to ensure all LEDs illuminate uniformly.

Engine management light illuminated due to AdBlue injector crystallisation or failing NOx sensors.

Typically appears

40,000-70,000 miles

What to inspect

Start the engine from cold and check the dashboard for the EML or an 'AdBlue system fault' countdown message. Listen for a lumpy idle during the first 10 seconds.