Headlamp cleaning system
Here you will find useful information and important tips relating to the headlamp cleaning system.
Important safety note
The following technical information and practical tips have been compiled by HELLA in order to provide professional support to vehicle workshops in their day-to-day work. The information provided on this website is intended for use by suitably qualified personnel only.
Headlamps which provide intensive light are more prone to glare through build up of dirt. For this reason, the legislator prescribes headlamp cleaning systems for such powerful lights, as well as automatic headlamp leveling. The cleaning principle of a "water jet" has long replaced the "wiper" principle for headlamp cleaning.
A complete HELLA headlamp cleaning system is made up of the following components:
The cleaning fluid is sprayed at high pressure in the form of cone-shaped drops onto the headlamp cover lens. The cone-shaped drops are formed by means of special whirl chamber nozzles.
The headlamp cleaning system is usually triggered together with the windscreen cleaning system. Every time the driver activates the windscreen washers, the headlamps are automatically cleaned at the same time. This coupling only takes place when the lights are switched on. When the centrifugal pump is triggered, this presses the water into a cylinder, the piston of which has a nozzle head attached and is extended against a pressure spring, bringing the nozzles into their working position.
Until the working position is reached, a valve ensures that the movement only is carried out first without any water escaping from the nozzles. When the working position has been reached, the valve opens and water is sprayed onto the headlamps. Once the pump has been switched off, the return spring moves the piston back into its initial position. One washing impulse takes approx. 0.5 s for stationary nozzles and approx. 0.8 s for telescopic nozzles (due to the time required for extension).
When some cleaning agents are used, excess dosing can result in heavy foam formation since this effect is exaggerated even more by the whirl chamber nozzles.
If the centrifugal pump does not work (noise can be clearly heard during normal operation) when the washing function has been activated, the voltage supply including the fuse must be checked.
If the water spray cone is only one-sided or extremely weak although the pump is working, this could be caused by the following:
Inverse polarity of the motor pump:
Check the polarity, since centrifugal pumps can work in both directions of rotation but with different hydraulic power.
System is not bled:
Bleed the system completely by activating the system several times without a break.
Hose is kinked or leaking:
Check the routing of the hose and change if necessary. Seal leaks and/or repair hose.
Nozzles or valves are blocked:
Remove foreign particles by rinsing the system.
Component parts are frozen up:
Increase amount of anti-freeze. Freezing will not damage the components, however.
If cleaning efficiency is still not as good as it should be, check the nozzle setting and/or set according to manufacturer's specifications.