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I would be very surprised if it is the LCM, there is a self test process. What has the garage checked?

For the post facelift there are two signals to each front indicator bulb from the LCM: 49VL_1 and 2 or 49VR_1 and 2. I would first be carrying out a continuity check of pins 5 and 6 at the headlight followed by putting 12V across them to see if the bulbs light up. This could also be done from the LCM pins to check the continuity at that end. Alternatively it seems the headlight pins are the same on each side, if the connectors are a physical match it's worth swapping them over and testing.

If they do replace the LCM and you still have the problem, what then?

take it to different garage, check headlights plug and reset lcm module . Lcm cuts power completely after certain amount of tries .

The garage may be very good at mechanical stuff..

Id' be going into the the actuations menu via diagnostics and telling the LCM to turn on specific lamps, if it still doesn't work if then check for voltage at the lamp and also a good ground, as it could be just that.. As Steve said above, there are for some reason two completely seperate feeds to the individual bulbs.

Mike

Cheers all most appreciated, Mike - just sending you an email.

No problem. Whereabouts are you, happy to have a look. I have all the gear.

Mike

Great thanks mate, South Manchester 50 mins or so

If I'm understanding you correctly what you are saying is one of the two indicator bulbs that is in one of your headlights is not lighting up but the other indicator bulb is. The garage you've been to is saying it's not a fault with the headlight unit, bulb or bulb holder but a faulty LCM. If all the above is true I wouldn't buy an expensive LCM I would rewire/tap into the working indicator's wiring to power the one that is not currently lighting up and turn off the bulb warnings with inpa/Carly etc. Might be a bit of a bodge but it's better than spending hundreds on a LCM which will also need to be coded to the car.

Andy, is it the same one on each side not working, ie inner/outer?

Mike

it's just the inner bulb of the left indicator that has the problem. All other lights I've checked and are fine. Cheers for all the info

You can use a second hand one but they need coding which the garage I doubt will do as it stored the car mileage and will through a tamper dot on the dash. Have they ran bmw software to identify the fault? What codes did it come up with.

Andy has just left mine, with the fault repaired.

I have no idea who the garage that had previously looked at it are, but I certainly wouldn't use them.. Will let Andy explain that bit.

Anyway, quick actuations check of all the LCM outputs and yes, no inner os flasher. Codes stored in LCM pointed to an open circuit in the flasher.

Up on the lift and accesses the back of the lamp, much easier than on the floor!

Back probed the feeds with power probe and still nothing. Disconnected headlight from the car and applied power directly with the probe, still nothing, so it's the headlight and not the LCM..

Pulled a spare indicatior bulb and holder from a headlight I had, was starting to remove the one from Andy's car when I realised it was loose... Half a turn clockwise, and voila, code's cleared and data streams monitored, all good.

Some garage... New LCM my @rse...

Mike

That's scandalous by the garage in question.

Thanks to Mike the car is fixed and really can't believe it after what the garage said about it all during the two times it's been in.

It looks as if they have snapped the inner plastic of the headlight unit as well trying to fit it back together last time and as a result the headlight does not seal properly now! So I now have a headlight with loads of moisture inside it and not sealed. Pretty F'd off with this.
In addition 2 bolts are missing from the headlight unit and it's been stuck back into place with silicone.

The first invoice on the initial fault finding states "indicator bulb replaced" clearly not what happened ! Even if it is a new bulb whoever installed it did not do it properly.

Either they were trying to pull a fast one with the LCM or were just that useless at fault finding and replacing the indicator!

Anyway, thanks to Mike it's all sorted, top bloke. Cheers Mike for helping me out, I'll be back for a few other things for the car as we discussed, new backbox being near the top of the list

I'll let you all know what the garage says tomorrow, I'm going to question them on what the hell has happened and what they are going to do about my ruined headlight !

Gather evidence to support your case. Remember when questioning to ask open questions and simply let them speak, more often than not they will dig a hole...

After explaining what actually happened with the headlight the garage are trying to do something about it. I'll see what this comes to this week.......

In the meantime they are trying to source a headlight unit for me. If anyone has a spare (unlikely) facelift xenon nearside headlamp knocking around then that would help me out loads. Even consider a pair and then sell what I have.

Any lighting upgrades / non oem to consider if I'm taking both lights out and replacing (last resort but may happen). Cheers all and thanks for helping me out.