Truck Headlamp Maintenance-3 Best Strategies
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Truck Headlamp Maintenance Strategy

The front combination headlamps of the truck, like human eyes, play the role of finishing the shape and appearance design of the whole vehicle. At the same time, as the main tool of night lighting, good working conditions play a vital role in night driving safety. Then, how to carry out daily maintenance on the headlamp combination headlights of the United truck? Let’s give you a basic explanation from several aspects:


Causes Of Fog And Frost In Headlamps

  1. When the headlamp is turned on and driving in rainy days, the air inside the headlamp becomes hot due to the heating of the light source. On the contrary, the surface of the headlamp becomes cool rapidly due to rain washing. At this time, the internal and external temperature difference leads to the formation of fog inside the headlamp.
  2. When washing the car, the heat in the engine compartment causes the lamp to become hot. At this time, washing the car will also produce a temperature difference, resulting in internal fog.
  3. The root causes of fog and water droplets: when the air temperature is 4 ℃, the maximum water vapor that can be accommodated is 6.36g; When the temperature is 20 ℃, the maximum water vapor in 1 cubic meter of air is 17.30g; It can be seen that at a certain temperature, the water vapor that the air can hold is certain. When it reaches saturation, the excess water vapor will condense, and enough water will condense to form fog or water droplets.

Judgment and measure Of Fog And Frost In Headlamps

Judgment Of Water Inflow

  1. Check the moisture condition of the mask surface.
  2. Check whether the appearance of parts is damaged when water enters.
  3. Check whether the assembly state of the rear cover is normal.
  4. Whether the parts are missing or damaged.
  5. Check whether there are abnormal changes in the wires.

Measures For Fog 

  1. When fog is generated on the windshield of the car, we will turn on the air conditioner to eliminate the fog; Similarly, when the headlamp generates fog, turn on the headlamp and the fog will dissipate slowly.
  2. The fog generated inside the headlamp is not a quality problem for the whole vehicle, but a normal phenomenon. Generally, the fog has little impact on the performance of the headlamp.

Methods To Avoid The Generation Of Fog And The Removal Of Water From Lamps

  1. It shall be avoided to wash the car or wash the lamps when the headlights are on (rainy weather is inevitable and not emphasized).
  2. Avoid driving in sections with too deep ponding (the wading depth depends on the design height of vehicle lamps and the wading speed of vehicles).
  3. Avoid that the lamp back cover and steering bulb holder are not installed in place after replacement; The inner surface of the corresponding sealing rubber ring shall be cleaned. There shall be no sediment or sundries on the rubber ring. The sundries or installation errors of the rubber ring cause the lax sealing of the lamps, resulting in the formation of water and fog.
  4. When fog beads are found on the inner surface of the lamp, continue to use it in the rain environment as far as possible. When the weather improves, turn on the high and low beams at the same time, Under normal circumstances, the fog will dissipate naturally after driving for 30-60 minutes (occasionally, the fog cannot dissipate completely, which depends on the water vapor density when the fog is formed and the speed is too fast, and the lamp temperature decreases. The driving time of the vehicle can be extended or the speed can be reduced appropriately).

Appearance Maintenance Of Lamps

  1. When the vehicle is driven in a poor environment for a long time, the driver feels that the illumination of the vehicle decreases significantly, indicating that a certain amount of dust or sediment has accumulated in the lamp mask, At this time, the lamp mask shall be cleaned in time (so as not to interfere with the normal illumination of the lamp and affect the heat dissipation, resulting in the deformation of the lamp). 
  2. The front mask of the lamp can be cleaned with a high-pressure water gun, but the inside of the back bumper cannot be used with a high-pressure water gun, so as to avoid washing down the lamp accessories (dust-proof, air blocking or other) and causing water to the lamp in the future.

Replace The Headlamp

  1. Low beam headlamp replacement: When the vehicle is implemented on the bumpy road for a long time, the service life of the bulb will decline sharply, so it is necessary to replace the bulb regularly; When replacing bulbs, standard H1 24V 70W bulbs produced by regular manufacturers should be used, such as Orsan and Philips, and non-standard high power, large wattage, modified xenon lamp, and other practices should be strictly used. After the bulb is replaced, the surface of the sealing rubber ring inside the rear cover and the corresponding edge of the shell shall be cleaned to prevent dust, sediment, and other sundries from contacting the sealing ring, resulting in the reduction of the sealing performance of the lamp. Screw it in place in the correct way.
  2. High beam headlamp replacement bulb: The replacement method of bulb and position is the same as that of the low beam bulb, and the precautions are the same.
  3. Bulb replacement of turn signal lamp and daytime running lamp: Turn signal lamp and daytime running lamp bulbs are standard 24v21w p21w bulbs. Customers are requested to replace the specified standard bulbs at the regular service station. Strictly replace high-power or non-standard installation size bulbs, otherwise, it will cause overheating inside the lamp and other defects. During the installation of the bulb holder, attention shall be paid to avoiding the decrease of product air tightness caused by dust or sundries between the sealing rubber ring and the shell.

Replace The Headlamp

To adjust the low beam lamp, first turn the electric adjustment switch of the lamp in the cab to adjust the light type modulation to the lowest point, then use a long cross screwdriver to align the manual low beam adjustment screw, and turn the two adjustment screws counterclockwise at the same time to move the low beam lamp line upward to a reasonable position; Adjust the light type clockwise to reduce the headlamp distance (the adjustment height shall be in strict accordance with the national standard or the national qualified vehicle testing factory).


The good maintenance of the headlamp not only ensures the beauty of the headlamp but also ensures the safety of use. I hope our united truck fans will remember the above tips for maintenance. With good consideration and care for products, United truck will give you beautiful work and life.

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