Schemes for switching on lighting devices are shown in fig. 1 and 2

The lighting system includes headlights, spotlights, fog lights, front and rear lights, reversing lights, cab and bed lighting, engine compartment light, lamps and a set of switching equipment (switches, switches, relays, etc.).

The headlight (Fig. 3) is of a rectangular type, which significantly improves the light distribution on the roadway.

The headlights have a European asymmetric lighting system, which eliminates the glare of oncoming drivers.

The front lights are arranged in one housing with direction indicators. Lenses for marker lights are white, direction indicators are orange.

The rear light has a position light and a red brake light, as well as a direction indicator with an orange lens.

The left rear light also has a white diffuser at the bottom to illuminate the license plate.

The fog lamp FG 152 is made with a white rectangular diffuser.

The headlight is equipped with a halogen lamp, which, together with a special diffuser, provides good illumination of the road in poor visibility conditions (fog, rain, etc.).

External lighting is controlled using switch 10 (see Fig. 2).

Switch handle has 5 positions

  • 0 - all off;
  • I — marker lights on;
  • II - parking lights and low beam are on;
  • III - side lights and high beam are on;
  • IV- side lights and high beam are on for working in flashing mode

The position IV of the switch is not fixed: when you remove your hand from the switch handle, the latter returns to its original position.

All five switch positions are marked with corresponding symbols to indicate which lighting fixture is on.

MAZ Headlight

Fog lights and spotlights are switched on by separate switches, and in the circuit for switching on spotlights, a blocking is used, which excludes the possibility of turning on the headlights in low beam.

Checking MAZ reverse light switches

During operation, it is necessary to monitor the cleanliness of the lenses and rinse or wipe them with a rag before leaving.

Dirty lighting devices have a sharp decrease in light output, which worsens both the visibility of the lamps and the illumination of the headlights of the road.

In such lighting devices as headlights, lanterns and ceiling lamps, under operating conditions, the reflectors darken or the housings and diffusers break.

When diffusers fail, they are replaced with new ones.

If the housings break and the reflectors darken, the entire device changes.

List of lamps used in lighting fixtures:

  • Headlight 8704.24 - А24-55-50
  • Fog lamp FG152 - HI type AKG24-70
  • Spotlight 20.3711 - HI type AKG24-70
  • Front lamp PF130B - А24-21-2
  • Rear light
  • FP130V-left - А24-21-2- 2 pcs
  • ФП130Г-right - А24-21-2- 2 pcs
  • Side direction indicator 14.3726 - А24-5
  • Identification sign lamp for road train PF233 - A24-5
  • Cab interior lighting plafond 11.3714 - A24-21-2
  • Sleeper cover PK124V - AC24-5
  • Reversing lamp ФП135Б А24-21-2
  • Blocks of control and signal lamps PD511B, PD512B - A24-2, 6 pcs. in block
  • Instrument cluster 13.3801 - A24-2 - 5 pcs
  • Pressure gauge UK 168 - A24 - 2 - 2 pcs
  • Speedometer SP 152 - A24 - 2 - 2 pcs
  • Alarm switch VK 422 - 24 - АМН24 - 3

It should be remembered that a dark coating sometimes appears inside the lamp bulb, which is the result of deposition of filament evaporation products on the bulb.

This phenomenon significantly worsens the light output, and it is advisable to change such lamps without waiting for their final failure.

This is especially important for headlights, on which the quality of road illumination depends.

If headlights are being replaced, then after installing them on the car, follow t adjust them according to the method described in the car's operating manual.

Switching equipment is quite durable and, as a rule, does not fail under operating conditions.

In case of failure of the product, it must be replaced, since switches and switches are not repairable.

Possible malfunctions of the lighting system and how to fix them

- Cause of failure


Headlights not working

- Fuses No. 17 and 18 for the high beam and No. 19 and 20 for the low beam have blown

Change fuses

- Lamps burned out

Replace bulbs

High beam warning light is off

- Fuse No. 17 blown

Replace fuse

The lamp burned out

Replace lamp

- The block of control lamps is faulty

Replace block or repair

Reversing lights do not turn on

- Fuse No. 11 blown

Replace fuse

- Faulty or not adjusted switch 11

Replace or adjust switch setting

If the relays P1, P4, P8 fail, they are checked, as indicated in the section "Electric torch device", and, if necessary, replaced.

In blocks of control and signal lamps against short circuits, if a non-standard fuse was installed, the current-carrying tracks of the printed circuit board may melt.

Track burnout is repaired by soldering or soldering copper wire.

If the reversing lights fail, check fuse No. 8, if it is good, check switch 2 (Fig. 4).

To check, it is necessary to remove the protective cover 3 from the switch (Fig. 4, a).

If there is voltage at the switch terminal where the white wire is connected, and the reverse lights do not light up when the gear lever is in the "Reverse" position, then you need to remove the switch and check it.

To check the serviceability of the switch, the “+” of the voltage source 26 - 28 V is connected with a wire with a clamp to one terminal of the switch, and the other terminal is connected through a control lamp to the “-” source (Fig. 4, b).

In this position, the control lamp should not light.

If you press on the switch ball in the direction of arrow A (Fig. 4, c) and drown it until it stops (approximately 1.5 - 2.5 mm), then the control lamp should light up. If the lamp does not light up, the switch is defective and must be replaced.

If the switch is OK, then its position is not adjusted on the gearbox cover.

Adjustment is made by installing or removing shims located on the threaded part of the switch.