Main beam dims

[drmuddle]

Hi, when I flash the main beam my headlamps dim? Any ideas please.
68 lhd earlybay.
Many thanks.

 

[rlepecha]

Can you clarify what you mean by dim? When you flash the main beam the H4 bulbs are switched to another coil to produce the different light profile, therefore the standard low beam pattern will now not be projected?

Or do you mean the sidelights dim when you flash the headlights? Do they stay permanently dim after flashing the headlights or only while the main beam is on?

 

[drmuddle]

Hi, the side lights remain on, when I pull back the stalk to activate the full beam the main beam dims momentarily. It's effectively working backwards?

 

[drmuddle]

Hi, any further advice anyone.

 

[mike202]

the steering column stalk toggles the relay between the two settings of main beam or dipped beam. You should hear the relay click when you pull the stalk back and release. You should have the blue light on the dash as well when on main beam.

 

[drmuddle]

Hi Mike, yes the relay is heard clicking. The blue light will remain on if I hold the stalk back but the lights dim rather than brighten . I've removed the relay, opened it up to visually see it working. All looks well, I've cleaned the contacts, sprayed it with electrical cleaner and re fitted. Still the same. I'll double check the earth to the lights and if this fails I'll try a new relay.

 

[mike202]

It sounds as though your relay is working ok. I'm not sure what you mean by dim though. The main beam is a bit brighter than the dipped beam 60watts and 55 watts IIRC.

Is the engine running when you're doing this as the battery could be going flat causing the bulbs to dim?

 

[drmuddle]

Hi Mike, it's the same if the engine is running.
The way that I understand the lights are: side lights, main beam and full beam.
So my main beam is on, normal night driving and a pull back my stalk to momentarily put on the full beam but instead they dim... Similar to putting my side lights on. Rather than a bright bulb they are a dim bulb. I've also replaced the bulbs and checked the earth behind each light.

 

[mike202]

Ok so it sounds like there's no power going to the full beam. I would check the fusebox first, and then work back from the headlight connectors to test for power.

The stalk switch must be doing something as it's switching the relay from dipped to full beam, the problem seems to be that no power is getting to the bulb :roll:

Just a matter of testing and ruling one thing after another out

 

[drmuddle]

Thanks Mike, I'll give that a go. How's Monty? Look forward to seeing you at the shows. [GRINNING FACE WITH SMILING EYES]

 

[mike202]

Monty's fine thanks I will be updating soon, as just renewed lower ply panels. Looking forward to getting to a few shows this year. Not sure which though :lol:

I like to get to Busfest in September.

Good luck with the lights, it can't be anything too difficult!

 

[drmuddle]

Just an update everyone, it was the relay at fault. Purchased the correct type from vw cool air. All working fine again!

 

[mike202]