SOLVED! - It's full on dip

[Roberltd2]

Hi folks,
My neighbour just called round to tell me that the lights were on, she thought I might have been in the Zed so didn't come round straight away. When I got outside, the headlights were on high (full) beam even though the light switch was in the "Off" position. This has happened to me twice before on starting the engine, once a couple of years ago and the second time was Monday night as I left work. On both occasions it seemed to sort itself out once I'd opperated the light switch and lever a few times. Tonight though I've not been able to fix it.
If the dip / full lever is in full position the lights go off, but if it's in the dip position full beams come on regardless of light switch position and whether the engine / ignition is on or off.
I checked the battery which was showing 12.79V, which I would think would be ok if it had been running the lights for some time. The battery (Yuasa YBX5110) was bought new in June of last year and the indicator on it is showing green.
I did notice tonight that one of the number plate bulbs has blown although this hadn't shown up on the dash.
Also noticed that there was a slight flicker in the overhead cabin light as I went to investigate tonight.
I do have an OBD2 car scanner although I've never used it, but I'll try and get the car over the mechanic tomorrow.
Just thought I'd share this dismal state of affairs with the Forum members in case any of you can offer any ideas as to what's going on.
Cheers,
Robert.

 

[markplant]

Could be a old battery causing issues or LCM

 

[oldgitdave]

Yes, I'd go with LCM too. Mine recently failed causing similar intermittant issues, headlights on with the switch in the off position. Also my indicators stopped working. Turned out to be corrosion on the circuit board.

 

[Roberltd2]

The LCM (light control module?) sounds like a good suspect and a good place to start looking. Battery was new last year so it shouldn't be that hopefully.
Is it difficult to remove the LCM?
Thanks for your help.
Robert.

 

[Roberltd2]

Dave, did you manage to find one second hand, buy a new one or did the old one clean up?
Robert.

 

[oldgitdave]

Dave, did you manage to find one second hand, buy a new one or did the old one clean up?
Robert.

Robert, the LCM is very easy to remove, just a couple of screws once you pry the aluminium facia off (or whatever your dash is made of). You then need to pull the LCM forward & lift a white lever to disengage the loom at the back. It's a bit fiddly but it can be done. Disconnect the battery first else you'll trigger the airbag light (tell me how I know :wink
I bought a secondhand one & fitted that. I used Realoem to find the right one as there are several different options. Everything returned to normal but the LCM carries the mileage & the VIN number so it'll cause a small tamper light to show on the instrument panel. I had to have it coded to my car to correct that. All good now though . Let me know if I can help further.
Dave

 

[Roberltd2]

Thank you Dave. More important info about things I'd not considered. I'm just having a quick coffee now and then I'll get on with it. The dash is aluminium. I'm just reading up some other posts on the forum about removing the driver's side of it.
Updates to follow...

 

[oldgitdave]

Thank you Dave. More important info about things I'd not considered. I'm just having a quick coffee now and then I'll get on with it. The dash is aluminium. I'm just reading up some other posts on the forum about removing the driver's side of it.
Updates to follow...

It's just the surround of the LCM, a very small section. Easily removed with those plastic panel removers. It's quite tight but levers off OK.
Keep us updated.

 

[Roberltd2]

Well, I've managed to remove the LCM. The good news is that the main board looks pretty clean with no sign of corrosion as far as I can see, but I'm unable to slide the board out as you did in your photos
View attachment 1
I thought maybe it would be worth checking out the switch assembly, but could not get it to lift out despite removing the centre screw and unlocking two of the lugs holding it in


So, I'm thinking now maybe I should put everything back together and see how (and if) things work, in the hope that contacts might have been cleaned up by unconnecting and reconnecting.
And also find out how to replace the number plate light.
Robert

 

[Roberltd2]

Why can't I ever seem to upload photos properly?

 

[enuff_zed]

Why can't I ever seem to upload photos properly?

LCM switch assembly.jpg

Don't try putting them in using the 'insert image' button above the text box; look down at the bottom left below the text box and you'll see an 'Add Files' button.
Click that and it should become clear.

 

[Roberltd2]

View attachment 1

 

[Roberltd2]

mmmm... I'm sure I haven't had this much trouble before. Should I have not nenamed the files perhaps?

 

[Roberltd2]

 

[Roberltd2]

 

[Roberltd2]

Previously, I hadn't put anything into the "File comment" box. Thanks enuff_Zed.

 

[oldgitdave]

Well it looks clean enough but that doesn't mean it's not faulty. I guess you could try a bit of switch cleaner, let it dry & see if there's any change. Mine was intermittent for a couple of months before failing completely. Shame you're not nearby because I've got a spare you could try, though it may not be the same spec.

 

[Roberltd2]

So the latest is that I've put the LCM and switch unit back together, plugged & screwed them back in and reconnected the battery. Predictably enough, the symptoms are exactly the same as before. I'd also replaced the blown bulb on the number plate. I thought these were sealed items but they're not, so I've achieved something today at least.
I noticed that as I reconnected the earth to the battery (having connected the +ve first) that there was a bit of sparking between the post and the lead. I hope this is normal, various circuitry coming back to life etc. Ignition was off at the time.

 

[Roberltd2]

Thanks for the offer to try out the spare unit by the way. I would definitely consider taking you up on it except I'd be stuffed if the main beams decided to stay on no matter what.
There is an LCM on ebay which looks identical going for £100 buy it now. Is this the going rate or are there better places to look d'you know?

 

[Spriteracer]

If you haven't already, try Quarry motors - they are a specialist BMW breaker. I have found them reasonably priced and usually a fairly quick turnaround. www.quarrymotors.co.uk