The BMW 4 Series facelift has been on public roads in Germany.

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From these photos, we can see that, superficially at least, the 4 Series update will be limited to a few tweaks to the front and rear bumper design, and new graphics for the both the headlamps and tail-lights.

Under the skin, the 4 Series should receive the same upgrades that were applied to the 3 Series range last year. This means that for some markets, the entry-level 4 Series coupe could be powered by the company's 100kW/220Nm 1.5-litre turbocharged three-cylinder engine.

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If the coupe follows the pattern laid out by the 3 Series sedan, there will also be 135kW/290Nm and 185kW/350Nm variants of the 2.0-litre turobcharged four-cylinder petrol engine, as well as a 240kW/450Nm 3.0-litre turbocharged straight-six.

The 3 Series range is also available with a 2.0-litre turbo-diesel in four output grades: 85kW/270Nm, 110kW/320Nm, 140kW/400Nm, and 160kW/450Nm. Rounding out the compression ignition offerings is a 3.0-litre straight-six with 190kW of power and 560Nm of torque.

It's not known if the 4 Series will be offered with the 330e's 185kW/420Nm plug-in hybrid drivetrain.

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Australia

Given that the 4 Series range made its initial debut a year after the closely related 3 Series models, it's likely that this update will debut internationally before 2016 is out.

For Australia, however, the updated 4 Series is likely to arrive sometime around the middle of 2017.