The forthcoming, W223-generation Mercedes-Benz S-Class has been spied on test again in Death Valley, California, and this time it’s been seen running with what appears to be its production facade. The development vehicle here wears the headlights and front grille which appear similar to those on the W223’s last sighting, though here they can be seen together with the shape of the front bumper more clearly seen.

As seen previously, the W223 S-Class will adopt the German automaker’s latest, more horizontal style of headlamp and tail lamp design already seen on models such as the W177 A-Class, V177 A-Class Sedan and the C257 CLS. The development car here also carries the large panel within its grille which is part of the car’s autonomous driving systems which will be developed with GPS integration to better handle critical scenarios, such as traffic lights and junctions, according to sources.

The flagship will also grow in its electrification, further improving on the capabilities of the current, W222-generation S560e plug-in hybrid. This present-day model pairs a 367 PS/500 Nm 3.0 litre turbo petrol V6 with a 90 kW/440 Nm electric motor for a total system output of 476 PS and 700 Nm of torque.

Both six- and eight-cylinder engines are expected to feature in the conventional internal combustion engined line-up, the former to include diesels while the latter will also include the range-topping AMG versions. A fully electric model in the form of the EQS is also in the works, one that will sit alongside the mainstream S-Class range, albeit with even more interior space from its MEA electric vehicle platform.

Though not official, the W223 could do away with the standard wheelbase version, leaving just the LWB for the flagship, Autocar reports. This is likely considered due to the W213 E-Class that is now 4,923 mm long, and the marque will be keen to put more clear air between this and its flagship; the W222 measures 5,246 mm long with a wheelbase of 3,165 mm.

Occupant comfort is paramount in the S-Class, and the W223 is expected to develop further on the Airmatic+ air suspension system, where it will work with a 48V architecture and a predictive, camera-based system to adjust parameters accordingly, the report added.

Inside, the W223 will feature two digital displays, the second to be a large, tablet-style item that will offer access to most of the car’s functions. A new model generation should also bring a fresh design for the interior and its upholstery.

The W223 is slated for launch some time in 2020, currently still with some way to go in its development. This forthcoming generation of S-Class, along with the EQS, will be produced at the marque’s new facility in Sindelfingen dubbed Factory 56.

GALLERY: W223 Mercedes-Benz S-Class spyshots