Smart ForTwo
The Renault three-cylinder turbo (identical to the Renault Twingo III unit) is the best engine Smart has ever fitted. Punchy, economical and reliable. The Brabus version (80 kW) adds even more driving fun. The clear recommendation for the Smart 453.
Finally forFun
109 hp Brabus cabrio — the most focused and emotional 453 variant. Motor1 summed it up perfectly: "Finally also forFun." The cabrio premium is worth it.
Engine Weaknesses 4
The known wastegate fault also affects the facelifted H4B. Moisture in the plastic housing destroys the electronics and crown gear. Renault has offered the wastegate as a separate spare part from 2020.
Symptoms: Yellow engine warning light, power loss, no boost pressure, limp mode
The DCT gearbox in the Smart 453 shifts at high revs, which reduces comfort. In stop-and-go traffic the clutch slips continuously in 2nd gear.
Symptoms: Harsh shifting, juddering on pull-away, clutch smell, delayed engagement, gearbox fault message
Isolated cases of coolant loss at hose connections. In the Smart with the engine at the rear and the radiator at the front, the coolant lines run the full length of the underfloor.
Symptoms: Dropping coolant level, coolant warning light, damp patches on hoses, steam from a hot engine
The lambda sensor can fail at low mileage. Affected vehicles fail the emissions test; fault code points to a defective sensor heater element.
Symptoms: Engine warning light, failed emissions test, increased fuel consumption, rough engine running
Vehicle Weaknesses 12
Vehicles built in November 2020 were bonded with non-specification adhesive. In a crash, the passenger airbag might be unable to use the windscreen as a backstop. Recall should have been rectified free of charge at a workshop.
Manufacturing defect in the front axle steering knuckle: the knuckle can break, leading to complete loss of vehicle control. Recall affected several model years; vehicles should have been inspected at a workshop.
On models from 2016–2019, failures of the emergency braking assistant were documented. Repairs were usually covered under warranty. On used vehicles outside warranty, repair costs are to be expected.
The 6-speed dual-clutch gearbox (twinamic) judders and bucks especially when pulling away in city traffic and in cold conditions. Mainly affects the 66 kW engine. Software updates help partially; at heavy wear, clutch replacement is necessary (approx. €3,500).
The rear brake drums of the 453 rust heavily on seldom-used vehicles. The rust is not always cleared by braking and can permanently damage the drum. A well-known problem particularly for city drivers with short standing periods.
Particularly model years 2015–2016 were delivered with weak batteries, and the 453 did not warn of lights left on. Many owners report battery failure after just 2–3 years. Regular checks before winter are recommended.
On the 453 cabriolet, the electric hood motor fails prematurely. The gearbox housing of the left motor frequently cracks. The hood then jams or can no longer be fully opened or closed.
On the 453 cabriolet, water enters along the lower edge of the rear window and at the transition between the roof and tailgate. Often the cause is sealant omitted at the spoiler screws during workshop work.
The Smart Media System touchscreen freezes and no longer responds to input. The known quick fix: pull fuse no. 26 (yellow 20 A fuse) from the glove box and reinsert after one minute. Software updates from the dealer provide a lasting fix.
As with its predecessor the 451, the front drop links wear and cause rattling noises over bumps and cobblestones. Cheap repair, but a typical MOT advisory from approx. 60,000 km.
Typical short-trip city use means condensation water in the exhaust system never dries out. The exhaust rusts from the inside and outside. Particularly visible at the rear silencer. Replacement required.
The AC evaporator becomes a breeding ground for bacteria and mould when the air conditioning is not regularly dried out with fresh air. Musty, stale smell when switching on the AC, especially after standing periods.