The headlights don't light up at night
At night, if the headlights are not on and you cannot drive on the road, first check whether the fuse is blown. When the headlight switch is turned on, neither the high beam nor the low beam lights up. First check whether there is a blown fuse in the fuse box, and then check whether there is any reason for the drop between the car light switch and the dimmer switch.
When the live wire of the dimmer switch is connected to the far and low beam binding posts with screws, the lights will be on, indicating that the dimmer switch is down for some reason; if they are overlapped and connected, the high beam will be on. Low beam is not bright. The fault is between the dimmer switch and the headlights or between the low beams. If the high beam of the headlight does not light up, check whether the high beam indicator light is on. If it is on, it indicates that the fault is between the wiring board and the headlight. If it is not on, it indicates that there is a fault between the wiring board and the dimmer switch. If only one headlight is on and the other is not, it may be that the filament is burned out or the wiring is broken, or the grounding is poor (the headlight brightness is weak).
Light bulbs often burn out
During the use of large and small light bulbs, the filament often burns out. The reasons are: the voltage regulator is faulty and the voltage is too high; the battery wires are in poor contact, causing the generator no-load voltage to be too high; there is a gap between the generator armature and the magnetic field coil. short circuit. If you turn on the light switch and the bulb burns out immediately, you should check whether there is an open circuit between the charging lines. If the bulbs often burn out, check whether the generator voltage regulator voltage is adjusted too high.
Tail light does not light up
When the car is driving, other lights work normally, but only the taillight does not light up. The reasons may be: the taillight filament is burned out, the taillight grounding is poor, or the taillight circuit is broken. When inspecting, you should first remove the taillight bulb and check whether the filament is burned out. If the filament is intact, use a test pen or screwdriver to scratch the tail light live wire terminal against the iron. If there are no sparks, it means there is a break in the tail light circuit. Find the break and connect the wires. If there are sparks, it means the tail light is poorly grounded. .
Brake light doesn't light up
When braking, the car's brake light does not come on. The main reasons include: burnt filament, poor grounding, malfunctioning brake light switch or a break in the circuit. When checking, first remove the brake light bulb and check the night filament. If the filament is intact, you can use a screwdriver or wire to connect the brake light live wire terminal and the ground while depressing the brake pedal. If there is a fire and the brake light does not light up, it indicates a poor ground; if there is no fire, It indicates that the brake light switch may be malfunctioning or there may be a break in the circuit. Then use a screwdriver or wire to short-circuit the two terminals of the brake light switch. If the brake light comes on, it means the brake light switch is faulty and should be replaced or repaired. If the brake light still does not light up, it means there is a break in the circuit. , find out and eliminate them.
Turn signal does not light up
When the left and right turn signal switches are turned, the turn signals are not on. The reason is: there is a break in the live wire from the flash relay to the steering switch, or the flash relay or the steering switch is faulty. The inspection steps are:
(1) Check whether the live wire of the flash relay has electricity. If there is no power, check whether there is an open circuit between the line and the power supply.
(2) If there is power, use a screwdriver to connect the two terminals of the flasher relay. If the turn signal lights up, it means that the flasher relay is faulty and should be replaced. If it does not light up, check the flasher relay. Open the flasher relay cover and check whether the coil and resistor are intact. If the resistor heats up and the contacts cannot be closed, press the movable contact; if the turn signal lights up at this time, it indicates that the relay is faulty. If the contact gap is too large, it should be adjusted. If the turn signal still does not light up when the movable contact is pressed to close the contact, use a screwdriver to short-circuit the contact. If the light turns on at this time, it means that the contact is oxidized.
(3) When the two terminals of the flasher relay are short-circuited with a screwdriver, if the turn signal does not light up, the turn switch may be faulty. During inspection, use a screwdriver to connect the hot wire of the steering switch and the left and right light wire terminals respectively. If the light is on, it means that the steering switch is faulty and should be removed for repair or replacement.
