Subcompacts (passenger cars with 85 to 99 cubic feet of interior volume) have been around for many years, gaining and losing
popularity based on gas prices. Modern subcompacts include the BMW mini, Chevy Aveo, Toyota Yaris and the Honda Fit. Although
these vehicles all have some specific repair methodology, fixing one actually is pretty straightforward. That may not be the
case with newer subcompacts and new breed of super minis, or city cars as they are known in Europe, that are finding their
way into garages over here. Some of these cars are unique, such as the Mercedes Smart Car. If you look around, you will see
quite a few of these vehicles on the road today.
Subcompacts, like any other vehicle, are built with safety in mind. The Smart Car for two (a two-seater) is equipped with
driver and passenger front airbags, side-impact airbags and a collapsible steering column. It also has a sophisticated seatbelt
system, incorporating belt pre-tensioners and a belt force limiter, designed to exert a controlled amount of pressure on the
occupant's chest while an impact is occurring.
Figure 1. Seats are a modular steel construction with headrests integrated into the seat itself.
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Additionally, the seats are a modular steel construction with headrests integrated into the seat itself (see Fig. 1). The
2008 version of this model earned the highest available ratings from the Insurance Institute for Highway Safety for front-
and side-impact crashworthiness. The Smart Car offers safety, efficiency and, for repairers, some repair challenges due to
its unique design. Here's some key areas you'll want to pay special attention to when this vehicle visits your shop.
Step 1: Identify materials 
Figure 2. The lightweight roof material actually is a module made of Makrolon specifically designed for use in automotive
glazing applications.
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The Smart Car's lightweight roof material actually is a module made of Makrolon, a polycarbonate plastic from Bayer Material
Science, specifically designed for use in automotive glazing applications (see Fig. 2). Covering an area of about 1.2 square
meters, it is to date the largest polycarbonate roof module in a production vehicle anywhere in the world.
The front mounting panel is a composite bolt-on panel. It acts as a headlamp-mounting panel/core support. In a fairly severe
front impact, this panel would probably sustain enough damage to warrant replacement. Like most plastic core supports, only
minor damage should be considered as repairable.
Doors are designed to bounce back from the abuse they will take in space-starved urban environments. The door skin is a flexible
poly material, similar to Saturn's plastic panels. It's very forgiving and will absorb most minor parking lot dings.
Step 2: Examine crumple zones and areas designed for strength
Figure 3. The front rail extensions are bolt on and are manufactured with convolutions, designed to crush during impact.
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Note the rail extensions in Fig. 3. These are bolt-on and are manufactured with convolutions, designed to crush during impact.
They likely will save frame rail damage under certain impact conditions. They will need to be examined closely in the event
of a front-end collision.
Figure 4. The inner portion of the windshield pillar is engineered with a rounded re-enforcing member to add strength.
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Refer to the cutaway view of the windshield pillar in Fig. 4 and particularly the design of the inner portion of the pillar.
It is engineered with a rounded re-enforcing member (in red), which adds tremendous strength to the panel when assembled.
Repairing damage in this area might present some challenges because of this design. Obviously, fixing a kink in the outer
panel may leave the inner panel damaged and weak, causing a possible safety issue later.
Figure 5. The doorframe is very rigid, with the hinges integrated into the doorframe and intrusion beam.
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One of the most interesting subassemblies on this vehicle is the door. The doorframe is very rigid, with the hinges integrated
into the doorframe and intrusion beam (see Fig. 5).
Doors frames need special attention. Because the skin is flexible, in the event of an impact to the door, special attention
should be paid to the frame and hinge area. Removal of the outer skin and careful inspection of the doorframe itself is highly
recommended.
Kinks or cracks would likely result in the replacement of the frame assembly. The entire side of the vehicle is basically
the door and door aperture, which adds strength. There is a body side and a door side to the hinge assembly, connected by
a pin and bushing. There are some very minor adjustments for door alignment that can be made in this area if they are needed.
Step 3: Mind the rear end
The engine of the Smart Car is rear-mounted, making this an area of particular interest in a rear-end collision. The cooling
modules are not located in the rear of the vehicle, so impacts to the rear or drivetrain area of the vehicle won't cause coolant
leak issues. The engine cradle is fairly large for a vehicle this small because it serves several roles. It adds rigidity
to the entire rear area of the vehicle and acts as a platform for all the mechanical and suspension components. It also is
modular and is fairly easy to remove and adds in vehicle stability and handling.
The rear bumper cover is made in sections. The center is a small cover over the rear bar itself, while the right and left
rear covers are huge and actually look more like the quarter panels rather than the bumper cover. These are made of a rubber-like
material and are repairable using standard plastic repair techniques.
The tail lamps also are mounted in this area. The rear impact bar is equipped with extensions that are convoluted. These,
like the front, are designed to crush in a rear impact.
Final word: It's a small world
Since larger, less fuel efficient vehicles probably will continue to disappear, smaller more fuel efficient cars will likely
begin to make up a larger segment of the vehicles on the road in the future. It is inevitable that your shop will begin to
see more and more of these types of cars.
As demand increases, new technologies will emerge. I suggest you make sure you are prepared and make it a point to allocate
time and resources for the training needed to fix these types of vehicles. They aren't just visiting. You can bet they're
here to stay.
