Questions and answers to the Maintenance and car control

driver presses the brake pedal, the shoes open and rub against the drum, which is connected with the
wheel. The wheel starts to slow down. These brakes are mainly used for our motorcycles, in passenger
cars they are used for rear axle. The disadvantages include: bigger weight and size
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Smaller braking effect
In longer braking the braking effect is lower due to the fact that the drum expands when exposed to
heat
More difficult check, or change of brake lining
(!) Why are disc brakes mainly used for front axle? When braking hard about up to 2/3 of the car weight
is transferred on the front axle, that´s why disc brakes are more effective on the front axle.
17. Describe the purpose of antilock braking system (ABS) of the car and how to
check its correct functioning.
ABS system is antilock braking system which prevents skidding when braking heavily. It ensures good
directional stability, manoeuvrability and permanent steering control of the car, especially in curves. The
wheels do not lock even during heavy braking – braking is interrupted and controlled by electronic
control unit which receives information from wheel speed sensors and controls the braking intensity.
In certain adhesive conditions, e.g. on frost, it significantly shortens the braking distance.
If the ABS symbol (red or yellow colou) does not light, when the engine is started, it indicates a faulty
bulb. The ABS symbol should go off after about 5 km/h, if there is a defect on ABS, the system is
automatically disconnected and the ABS symbol is lit.
(!) Is it possible to proceed driving when the ABS symbol is on? If the ABS symbol is on, it is possible to
proceed, but the driver must take into account that ABS is no longer functional for heavy braking, the
defect must be repaired at the garage.
18. Describe the most frequent manifestations of the wrong streering axle geometry.
Wheel geometry is the basic position of the steering wheels against the axle. It affects manoeuvrability of
the car, directional stability, it returns wheels to the straight direction. Parameters to be set on the steering
axle are:
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Toe - defines backlash in the steering