No nearside main beam

[Baycott]

My van (Hymer B574DL) has just passed it's MOT but the technician told me the main beam on the near side isn't working. He was going to fit a new bulb but, when he removed the headlight, he realised it was an LED. Does anyone have any idea what could cause this. I have replaced the wiring looms (twice) The second time with the upgraded wiring so I don't think it's that.

 

[Gellyneck]

I pulled all the 7.5A fuses from that box and they're all fine so I'll check the relays when the weather improves.

That's a bummer!

 

[Taran_Las]

Thanks for that info Taran_Las for future reference would you be in a position to post a photo of the offending relays as I’m thinking I may like to protect them if possible

I'm afraid I can't provide photos as I've just sold (part ex'd) the Hymer. As the OP has a left hooker, behind the nearside headlamp you'll find a 'two relay' block, probably cable tied to something. Mine wasn't a tidy installation. I suspect someone had been there before me to set the headlights for importation. Don't be surprised if the block is just dangling. You don't need to remove the headlamp to get to them.

btw - The headlamps don't have dip & main-beam bulbs. A shutter obscures part of the bulb thereby producing a dipped beam. When you activate the main-beam switch, the shutter is moved by a solenoid driven mechanism exposing the whole bulb. You can hear the solenoid operating if you are in front of the van with the engine off. If the relay is kaput, you won't hear the solenoid moving.

Hope this helps.

Thanks to Lenny HB for giving me the heads up on the main-beam operation.

 

[Speve]

I'm afraid I can't provide photos as I've just sold (part ex'd) the Hymer. As the OP has a left hooker, behind the nearside headlamp you'll find a 'two relay' block, probably cable tied to something. Mine wasn't a tidy installation. I suspect someone had been there before me to set the headlights for importation. Don't be surprised if the block is just dangling. You don't need to remove the headlamp to get to them.

btw - The headlamps don't have dip & main-beam bulbs. A shutter obscures part of the bulb thereby producing a dipped beam. When you activate the main-beam switch, the shutter is moved by a solenoid driven mechanism exposing the whole bulb. You can hear the solenoid operating if you are in front of the van with the engine off. If the relay is kaput, you won't hear the solenoid moving.

Hope this helps.

Thanks to Lenny HB for giving me the heads up on the main-beam operation.

Thanks I was aware of the bulb and shutter I will investigate the solenoid and relay

 

[Baycott]

I had a similar problem and it wasn't the wiring loom. There are two relays on the offside which operate the main beam. They were installed in such a way they would allow water in. They were completely rusty, one more than the other. If that is the cause of the problem (you can easily tell by removing them) let me know and I can send you a set of new ones.

I've checked the relay(s) but, stupidly, just swapped them over instead of trying them individually. Swapping them made no difference, still no main beam on left side. I've put it all away now so Monday (it's going to rain tomorrow and we're going out on Sunday) I'll have another go, trying one at a time (could be the holder at fault?). They weren't fixed to anything so I'll have to find a way of securing them. There is no sign of corrosion so that's a good sign I guess.

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[Taran_Las]

The corrosion will be inside the plastic casing. Can you hear the solenoid engaging?

 

[Baycott]

I think both relays are working as, when I swapped them over, the problem remained. Therefore each relay has operated the right hand light.

 

[Landy Andy]

Are you getting the correct values to the relays?

 

[Baycott]

Are you getting the correct values to the relays?

Sorry Andy, do you mean voltage? I haven't got that far yet. I'll do more testing on Monday.