First introduced in 2017, the third-generation C257 Mercedes-Benz CLS has been given a subtle nip and tuck, giving the handsome four-door coupé a blink-and-you’ll-miss-it exterior refresh, some added paint and upholstery options and a new mild hybrid diesel engine.

On the outside, the changes are limited to a new front fascia with redesigned air intakes, twin corner louvres and a chrome front splitter, with AMG Line models getting a unique bumper sporting a revised “A-wing” design, a slimmer and wider centre inlet and gloss black corner fins.

All cooking models also get a rather chintzy new grille with lots of tiny chrome three-pointed stars, first seen on the new C-Class. The range-topping AMG CLS 53 4Matic+, meanwhile, ditches the classy dual-bar grille for Affalterbach’s ostentatious Panamericana vertical slats.

Beyond that, there are new wheel options – including redesigned 20-inch multi-spoke rollers for the AMG Line – and new spectral blue metallic paint. Step inside and you’ll find new steering wheels lifted from the facelifted E-Class, one of them being a double-spoke flat-bottomed AMG Line item. That’s literally it.

Customisation options have also been increased under the designo banner, with new jupiter red, cashmere white magno and emerald green paint options. The two-tone Nappa leather upholstery, meanwhile, is now available in classic red and black, saddle brown and black, tartufo brown and black, deep white and black, and yacht blue and black.

As for the CLS 53, a new AMG Night Package II adds a darkened chrome grille and badging, while the AMG Dynamic Plus Package throws in red brake callipers, an AMG Performance steering wheel and an additional Race drive mode with a new Drift mode function.

Mercedes is also offering 300 units of the CLS 53 Limited Edition, offered in either cashmere white magno with metallic grey side stripes or selenite grey magno with black stripes. Included with the car are black 20-inch five-twin-spoke alloys with a machined rim, both Night Packages, the Dynamic Plus Package, AMG logo floor projection, black and silver two-tone Nappa leather upholstery, carbon fibre interior trim and Dinamica microfibre on the steering wheel.

While most of the engine lineup is the same, the CLS 300 d 4Matic gets a new mill – a 2.0 litre four-cylinder turbodiesel with a 48-volt mild hybrid system. The OM654M receives a new crankshaft (which increases the stroke by 1.7 mm to 94 mm and the displacement by 43 cc to 1,993 cc), a higher injection pressure of 2,700 bar, twin variable geometry turbochargers and sodium-filled piston cooling ducts to dissipate heat.

Altogether, the oil burner makes 265 PS and 550 Nm of torque, with an additional 20 PS of boost coming from the integrated starter/generator (ISG), which also allows for an electric air-conditioning compressor. The emissions equipment has also been improved and includes a close-coupled nitrous oxide storage catalytic converter, a specially-coated particulate filter and a second selective catalytic reduction system.

Fuel consumption is rated at between 5.8 to 6.6 litres per 100 km on the WLTP cycle, while carbon dioxide emissions range from 153 to 172 grams per kilometre depending on the selected options. Other engine options include a less powerful 194 PS version (without the ISG) in the CLS 220 d, a 330 PS 3.0 litre straight-six diesel in the CLS 400 d, a 299 PS 2.0 litre petrol four-pot in the CLS 350 and a 3.0 litre mild hybrid petrol straight-six with either 367 PS (CLS 450) or 435 PS (CLS 53).

The mild tweaks go on top of the comprehensive technological update introduced last summer, which added the Mercedes-Benz User Experience (MBUX) infotainment system with an Energizing Coach wellness function. There’s also an upgraded Active Park Assist that can recognise painted floor markings and an improved display for the 360-degree camera system.

Safety systems have also been improved, with autonomous emergency braking now detecting oncoming vehicles at junctions when paired with the Driving Assistance Package. The Distronic adaptive cruise control is also able to slow down for corners, highway exits, roundabouts, toll booths, T-junctions and speed limits based on navigation data, and if the Driving Assistance Package is selected, it will even slow down for traffic.

Another new feature is Active Stop-and-Go Assist as part of the Driving Assistance Package, which can keep the car in lane and at a set distance from the car in front at speeds of up to 60 km/h. The system will also move over for emergency vehicles and use swarm intelligence to find its bearings among surrounding traffic on highways. The car can resume driving automatically within a minute of coming to a stop.