The electrical system of the MAZ vehicle has a rated voltage of 24 V. The on-board network of the vehicle is made according to a single-wire circuit
The negative terminal of the batteries (AB) is connected to the vehicle ground through the mass switch (frame, power unit, generator and cab). The AB positive terminal is connected to the vehicle's on-board network through the main 60 A fuse.
Two-wire connected:
- —portable lamp socket in cockpit
- - cockpit lights
- —heater fan motors
- - independent heater
- - tachograph
The main fuse is designed to protect the battery and generator from short circuit and polarity reversal when the engine is started from an external source and is not further considered as a fuse. (On vehicles with MAN engines, the 60 A fuse is shunted with a jumper with a cross section of 2.5 mm 2, therefore, it does not perform the functions of protection against short circuits (short circuit) and polarity reversal, but is used as a connecting panel for wiring) .
From the 60A fuse (on the side of the generator connection), all consumers of electricity are powered (with the exception of the alarm, which is connected directly to the battery) and additionally have their own fuses.
The starter and instrument switch, the main light switch, the starter relay and the ground switch winding are not fused.
All fuses are located in three blocks:
- - fuses 60 A and 30 A, 1 each - in block 111.3722
- fuses 6 A - 21pcs - in fuse and relay boxes 23.3722; 23.3722-01; 23.3722-02; 23.3 722-03
- - fuses 16 A - 1 pc. and 8 A - 9 pcs. - in the fuse box PR 112.
The purpose of the fuses (stripped circuits) and their ratings are shown in the tables:
Assignment of fuses in block 111.3722
60 A - main fuse
30 A - power supply for an independent heater, PZD technological equipment
Assignment of 6 A fuses in fuse and relay boxes 233722, 233722-01, 233722-03
No. - No. - wires - power circuit
- 1 - 127 - Parking brake warning lamp relay, voltage indicator, speedometer, tachograph
- 2 - Sound signals
- 3 - 57 - Stop signals
- 4 - 90 - Windshield wiper, washer
- 5 - 120 - Reversing lights, inter-axle and inter-wheel locks, engine light, semi-trailer steering axle lock, hitch light
- 6 - 162 - Mirror heaters, trailer lights
- 7 - On-board control system power supply
- 8 - P51 - Instrument lighting
- 9 - 55 - Fog lights
- 10 - Cch.52 - Marker lights, right
- 11 - D.52 - Side marker lights, left
- 12 - Ф.56 - Dipped beam (left headlight)
- 13 - F.56 - Dipped beam (right headlight)
- 14 - 53 - Additional driving lights
- 15 - K.54 - High beam (right headlight)
- 16 - Z.54 - Main beam (left headlight)
- 17 - D.80 - Heater fan
- 18 - F.79 - Alarm
- 19 - K.78 - Direction indicators
- 20 - P.31 - Pilot lamps, indicators (instruments) of the main shield
- 21 - 50 - Rear fog lights
Assignment of fuses in block PR 112
|
№ |
denomination |
№ п |
Power circuit |
|---|---|---|---|
|
1 |
16 А |
|
Reserve, technological equipment |
|
2 |
8А |
valve |
cooling fan clutch |
|
3 |
8А |
Г.172 |
Body lighting. control block Heater 15.8106-01 or Webasto |
|
4 |
8А |
Кч.179 |
Fuel heaters |
|
5 |
8А |
Р.171 |
Radio, timer |
|
6 |
8А |
Г.59 |
Cabin lights |
|
7 |
8А |
3.131 |
Portable lamp socket in the cab, pneumosignal, refrigerator |
|
8 |
8А |
|
Reserve |
|
9 |
8А |
С.133 |
Level sensors, air dryer, additional instrument panel, technol. Obor. |
|
10 |
8А |
О.161 |
Engine stop valve |
Assignment of relays located in blocks 23.3722, 23.3722-01, 23.3722-02, 23.3722-03
Relay type 901.3747-11
Relay No. - Consumers
- K1 - Sound signals
- K2 - Reversing lights
- K3 - Blocking of the "ground" switch
- K4 - Brake lights
- K5 - Onboard control system 23.3722, 23.3722-02
- K6 - Dipped beam headlights
- K7 - Blocking additional high beam headlights
- K8 - Marker lights
- K9 - Driving lights
- K10 - Electric torch device (resistance shunt)
- K11 - Electric torch device (generator blocking)
Location of electrical equipment
Name - Location
Sensor for turning on the control lamp for blocking the cross-axle differential VPST (MM 125D) - On the beam of the middle and rear axles
Sensor for switching on the cross-axle differential lock (MM 125) - On the pneumatic cylinder for switching on the middle axle lock and transfer case
Valve for switching on the cross-axle differential lock KEM-07 (P30.131.01) - On the left side member in the area of the rear axle
Valve for switching on the center differential lock KEM-07 (P30.131.01) - On the left side member in the area of the middle axle
Sensor for turning on the parking brake warning lamp DADV (MM124D) - On the two main parking brake drive valves
Sensors aemergency air pressure in the pneumatic brake system DADV (MM124D) - On the receivers of the front and rear circuits of the pneumatic system or on the sensor brake block
Air pressure sensors in the pneumatic system of the brakes MM370 - On the receivers of the front and rear circuits of the pneumatic system or on the block of brake sensors
Brake signal sensors - VPST (MM125D) - On the brake valve, on the trailer brake control valve or on the brake sensor unit
Engine stop solenoid 15.3747, PC330 - Outside, on the front panel of the cab, on the left under the lining
Pneumatic signal solenoid valve 16.3741 - Outside, on the left base of the cab
Relay of turns RS951A, PEUP6 - In the cab under the additional instrument panel
Wiper motor 13.5205 - Inside the cab, on the front of the cab, on the right
Washer motor - On the washer reservoir
Fuse and relay box 23.3722; 23.2722-01; 23.3722-03; 23.3722-04 - In the cab, in the central part, under the hinged panel cover
Wiper breaker relay 461.3747 - On the fuse and relay box
Range interlock relay 6312.3747 - In the cab on the right, under the flap of the instrument panel, under the flap of the fuses and relays
Fuse box Pr112 - In the cab on the right, under the hinged cover of the instrument panel.
Fuse box 111.3722; Starter relay 738.3747-20; Additional resistance EFU_12.3741000; Lantern FP12G; Relay signaling device 733.3747-10; Relay-interrupter of a control lamp of a parking brake RS493; Portable lamp socket - On the hinged fuse and relay panel
Electrical connectors (connecting the tail light harnesses) - In the junction box, at the rear of the left side member
Electrical connectors (connecting the side turn signal harnesses) - Inside the instrument panel on the left and right
Electrical connectors (connecting the side marker harnesses) - In the junction box, at the rear of the left side member
Electrical connector X62 (battery switch connection) - In the battery container
Scheme of electrical connections is "here"
Possible malfunctions of electrical equipment and solutions
Cause (Remedy)
Beeps don't work:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Faulty steering column switch
Check the function of the switch, replace if necessary
- Faulty switching relay
Check that the relay is working, replace the relay if necessary
- Sound signals are faulty
Check signal functionality, replace if necessary
Cab light does not work:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuses. If the fuse is defective, repair the short circuit in the circuit, replace the fuse. Replace pump
The engine light does not work:
- open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check that the fuse is working; if the fuse is defective, eliminate the short circuit in the circuit, replace the fuse
- Faulty light switch
Check the function of the switch, replace if necessary
- Destruction of the filament
Replace lamp
Pneumatic signal does not work:
- Open circuit of the valve, short circuit. Defective steering column switch
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Faulty valve
Check the condition of the valve, replace if necessary
Mirror heating not working:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, eliminate the short circuit in the circuit, replace the fuse.
- Faulty mirror heating switch
Check the function of the switch, replace if necessary
- Faulty heating element
Check the operation of the heating element, if not need - replace
Reversing lights not working:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness.
- Faulty reverse signal switch
Check sensor performance, replace if necessary
- Faulty switching relay
Check that the relay is working, replace the relay if necessary
- Destruction of the lamp filament
Replace lamp
The cross-axle differential lock valve does not work:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Faulty switch
Check the function of the switch, replace if necessary
- Faulty valve
Check valve operation, replace if necessary
The center differential lock valve does not work
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
Brake lights not working:
- Faulty switch
Check the function of the switch, replace if necessary
- Faulty valve
Check valve operation, replace if necessary
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Faulty brake light switch
Check sensor performance, replace if necessary.
High or low beam headlights and the corresponding control lamps do not work:
- Faulty switching relay
Check relay performance, replace if necessary
- Destruction of the lamp filament
Replace lamp
The main light switch is faulty. Steering column switch faulty:
- Check the reliability of the contact in the detachable connections.
- Check the integrity of the wiring harness.
- Check the fuse is good. If the fuses are defective, eliminate the short circuit in the circuit, replace the fuse
- Check if the switch works, replace if necessary
- Open circuit, short circuit
Check the function of the switch, replace if necessary
The marker lights do not work**:
- Faulty switching relay
Check relay performance, replace if necessary
- Destruction of the lamp filament
Replace lamp
- Faulty main light switch
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Open circuit, short circuit
Check the operation of the switch, replace if necessary
Rear fog lights and warning lamp do not work:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuses. If the fuses are faulty, eliminate the short circuit in the circuit, replace the fuse
- The main light switch is faulty.
Check the operation of the switch, replace if necessary
Faulty rear fog light switch:
- Destruction of the lamp filament
Check the function of the switch, replace if necessary
Replace lamp
- Faulty switching relay
Check that the relay is working, replace the relay if necessary
- Destruction of the lamp filament
Replace lamp
Turn indicators not included:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness.
- Faulty steering column switch
Check the operation of the switch, replace it if necessary
- Faulty relay breaker The PC951 relay has automatic short circuit protection (short circuit). When shorted in one of the sides, the relay turns off the direction indicators
PEUP6 has four independent channels: LB of the tractor, LB of the tractor, LB of the trailer, LB of the trailer. In the event of a short circuit in one of the channels, the rest remain operational
Check the operation of the breaker relay, if necessary, replace it
- Faulty alarm switch
Check the operation of the emergency switch, if necessary, replace it
- Destruction of the lamp filament
Replace lamp
The control lamps of the direction indicators of the tractor or trailer do not light when the PC95IA relay is operating (clicks are heard) and the relay / PEUP6 (the buzzer is buzzing)
Open circuit in the circuits of control or signal lamps of direction indicators:
- Broken threads of control or signal lamps
Check the reliability of the contact in the detachable connections. Check wiring harness integrity
Replace lamps
The door open buzzer does not work when the rear fog lights are on and the starter and instrument switch key is removed:
- Open circuit, short circuit
Check the fuse is good. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Faulty rear fog light switch
Check the function of the switch, replace if necessary
- Faulty limit switch
Check if it works, replace if necessary
- Faulty signaling relay
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- The gap between the left door and the doorway in the area of the limit switch installation has been increased
Adjust gap in doorway or adjust limit switch
Check the operation of the switch, replace if necessary
Wiper not working:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Faulty steering column switch
Check the operation of the switch, replace if necessary
- Faulty wiper relay
Check the operation of the breaker relay, if necessary, replace it
- Faulty wiper gear motor
Check the operation of the gearmotor, replace if necessary
Wiper motor is overloaded. When turned on, noise and rattle are heard, then it turns off (the thermal fuse has tripped):
- Rods are hooked on the cab parts
Ensure clearance between the rods and cab parts
- Traction jammed, brushes frozen
Ensure clearance between rods and cabin parts, eliminate freezing
Window washer not working:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Faulty steering column switch
Check the function of the switch, replace if necessary
- Faulty washer pump
Check pump performance, replace if necessary
Indicators do not work: fuel level, coolant temperature pressure, pressure in the pneumatic system*:
- Open circuit, short circuit. Faulty sensors
- Check the reliability of the contact in the detachable connections.
- Check the integrity of the wiring harness.
- Check fuses F20, F9. If the fuses are defective, repair the short circuit in the circuit, replace the fuses.
- Check the functionality of the sensors, replace if necessary
Tachometer not working:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse F20. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- - Faulty tachometer. Open circuit from the "~" terminal of the generator to the tachometer
- - Faulty geneErator
Replace tachometer
Check circuit in harnesses from alternator to tachometer
The blinking mode of the brake indicator lamp does not work:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. In the event of a fuse failure, eliminate the short circuit in the circuit, replace the fuse
- Faulty relay-breaker of the control lamp
Check the operation of the relay-breaker, in case of a malfunction, replace it
- Faulty parking brake sensor
Check that the sensor is working, if it is faulty, replace it
Heater motors do not work:
- Open circuit, short circuit
Check the reliability of the contact in the connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Faulty switch
Check that the switch is working, replace if it is faulty
- Faulty motor
Check the serviceability of the electric motor, in case of a malfunction, replace it
The warning lamps do not work: air pressure, emergency pressure clogging of the differential locks:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuses F20, F9. If the fuses are defective, repair the short circuit in the circuit, replace the fuses
- Malfunction of the corresponding sensors
Check that the sensors are in good working order, in case of a malfunction, replace them
- Destruction of the filament of the corresponding control lamp
Replace pilot lamp
Dehumidifier not working:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harnesses. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Faulty air dryer
Check the condition of the dryer, in case of a malfunction, replace it
The socket in the cab does not work:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuses. If the fuse is defective, repair the short in the circuit and replace the fuse
Radio does not work:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuses. If the fuses are faulty, eliminate the short circuit in the circuit, replace the fuse
- Faulty radio
Check if the radio is working.
Starter does not turn on:
Open circuit, short circuit. Faulty starter intermediate relay. Faulty starter and instrument switch. Faulty starter
- Check the reliability of the contact in the detachable connections. Check wiring harness integrity
- Check starter intermediate relay, replace if necessary
- Check the operation of the starter switch and instruments, in case of a malfunction, replace it
When the mass is turned on, the voltage arrow remains in place:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse F1. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
When the engine is running, the generator set health indicator lamp is on:
- Faulty generator
Repair or replace the generator.
The ground switch does not turn on from the cab:
- Open circuit. Power button broken
Check the reliability of the contact in the detachable connections. Check wiring harness integrity
- Faulty short circuit switching relay
Check if the button is working, replace it if it's broken
- Burning battery switch contacts
Check that the relay is working, replace it if it is faulty. Strip switch contacts
Speedometer not working:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit in the circuit, replace the fuse
- Faulty speedometer
Check that the speedometer is working, replace if it is broken
- Faulty sensor
Check that the sensor is working, if it is faulty, replace it
The backlight lamps - pointers and switches do not work:
- Open circuit, short circuit
Check the reliability of the contact in the detachable connections. Check the integrity of the wiring harness. Check fuse. If the fuse is defective, repair the short circuit, replace the fuse
- Faulty backlight rheostat
Check if the backlight rheostat is working
- Faulty switching relay for side lights
Check that the relay is working, replace if it is faulty