Dim headlights troubleshooting

Hello!

My headlights, at least low beam, hard to say about high beam they might just suck big time, are dangerously dim, I had to drive behind a car and follow his back lights to be able to survive back home.

Possible hint is that my neighbor said my back lights are brighter than cards around me. Any suggestions how to proceed? 12V battery is new. Do you know a topic here about the subject (non HID)?

I’m wondering that I need to figure our first if I have HID headlights but I doubt that very much, and maybe to measure voltage for the bulbs. Suggestions from where I should measure the voltage, directly to the headlamp unit? It seems both lights are equally dim, I can watch straight to them without problems.

 

Right, after some digging:

• My headlights are regular H4, megalite brand.
• Fusebox measurement for low beam gives 11.55 Volts.
• After cleaning up Android Light Meter show increase from 550 to 580 engine down so about 6%
• Starting the car and engine running shows max value of 1200 so doubling the lux (lux but this is very much relative result), comparing to my neighbors car (Opel Astra) gives max value from about same distance quite close of 3000.
• Plastic covering the headlamp looks a bit scratched but not too bad.

 

Hi andrewclaus,

I can’t answer to the question ”did it start suddenly” because I noticed this only the moment snow smelted away and it was dark. The snow makes even the dim lights to be enough, but I do remember thinking at one point that my car lights are ok but not great during snow period.

Great to hear they have common grounding point that makes this problem more likely. I need to study a bit before I understand the rest you said. Talk to you later, thx!

 

Do I understand correctly: The DIM relay puts the lights to day time mode if light are not witched on and when rotating lights to on position full lights are on use?

I can’t see any difference in light power when switching lights on or off.

Edit:
Right I got it wrong: high to low beam relay (DIM)

It is just this text that made it sound that there is a spcial daytime lightmode when lights are not turned on.
"When power SW is at IG ON position and the vehicle is ready to drive (READY lamp on the display in combination meter is
on), releasing parking brake makes signal go into TERMINAL PKB of body ECU. In this condition, when light control SW is at
Off/Tail/AUTO position (Headlight is not lit), body ECU sends daytime operation request from TERMINAL DRL/DIM to
daytime running light relay. As a result, daytime running light relay duty–operates headlights (Dimmer than regular lighting)"