Regularly check installation of light of headlights on your car, for example before checkup passing. Besides, check a condition of lighting before each trip.

For this purpose include ignition and in turn turn on the dimensional, near and far light, and also fog lights. Behind the car lamps of a backing, the lighting lamp of registration plate and back fog lamps have to work regularly. In the car always there has to be a set of lamps for replacement.

Fig. 9.16. The spare set of lamps always has to be in the car. It contains not only the most important spare lamps, but also safety locks

   In the car there has to be the following set of spare lamps (fig. 9.16):

– halogen lamp of H7, 55 W (near and far light);

– halogen lamp of H1, 55 W (fog light);

– halogen lamp of N, 6 W (dimensional / parking light);

– a round lamp of P or PY, 21 W (the forward and back index of turn with a flask of white or yellow color);

– round lamp P, 21 W (backing lamp, back fog lamps);

– round lamp P, 21/4 W (braking signal, dimensional/parking light);

– round lamp of R, 5 W (tail light, parking light);

– a sofitny lamp With, 5 W (illumination of registration plate);

– a sofitny lamp With, 10 W (illumination of salon, a luggage carrier);

– light-emitting diodes (external rear-view mirrors, additional signal of braking).

Fig. 9.17. Xenon lamps serve all term of operation of the car. If necessary replacement should be made on STOA as because of existence of the contacts which are under high voltage and danger of explosion independent replacement is complicated

The latest and at the moment the best development in lighting engineering — headlights with gas-discharge (xenon) lamps in the case from quartz glass (fig. 9.17). The light source is served by gas xenon and particles of various salts of metals. The electronic block of inclusion lights this mix a short impulse up to 28 000 V, between electrodes of a lamp the arc category is formed. It replaces an incandescence spiral which was applied still.

Advantage of such lamps that at consumption of energy with a power only 35 W the xenon lamp shines twice more brightly than the halogen glow lamp in 55 W. It has also bigger service life. Replacement of gas-discharge lamps is possible, but usually in it there is no need. Xenon lamps serve all term of operation of the car. If necessary replace such lamp with STOA.

Other advantage is the pleasant luminescence of a lamp as close as possible to daylight. Thanks to it the best and brighter lighting of the road ahead and sideways is provided, especially when passing turns and lighting of the adjoining roads.

TECHNICAL DICTIONARY Adjustment of range of light According to legislative rules light of headlights of the car in the loaded state has to be adjusted so that it did not blind oncoming vehicles. Light of halogen lamps. On E-class models with halogen headlights range of light is regulated by the three-position regulator on the dashboard. For this purpose each headlight is equipped with the pneumatic mechanism of the proofreader which at change of position of the regulator operates due to the depression which is formed at an inlet cycle of the engine. The regulator provides giving depression to the proofreader between 0,4 bar (situation "0") and 0,05 bar (situation "3"), defining thus its course. Light of xenon lamps. As danger of dazzle of counter transport from light of xenon headlights is especially high, headlights depending on loading of the car are regulated automatically.

Fig. 9.18. Principle of action of system of adjustment of range of light of headlights: 1 – a vacuum hose from an inlet pipe or the vacuum distributor; 2 – distributor; 3 – the vacuum regulator near light switch; 4 – mechanism of the proofreader of headlights right; 5 – mechanism of the proofreader of headlights left; 6 – shtekerny connection

Sensors on forward and back axes define each change of position of the car of rather horizontal axis and transfer information to the control unit of adjustment of range of light of headlights (fig. 9.18). The block is under a back seat. The current provision of headlights is defined in the control unit thanks to the potentiometer installed in mechanisms of the proofreader of headlights. The control unit gives team about change of provision of headlights with a delay when from the moment of change of position of the car there passes certain time.

Glow lamps of external lighting for passing, dimensional beam, back lamps and signals of braking are controlled by this device. At burn-out of this or that lamp the control lamp which burns until this consumer is included lights up. At burn-out of lamps of lamps of signals of braking the control lamp burns before switching off of ignition.

The control device distinguishes violation in this or that chain if in it too small current proceeds. At higher current, for example at turning on of the trailer, it does not lead to false operations.