Jump to content
Sign in to follow this  
roo

E34 OBC Errors - Tail, Lisc Plate, Dip Beam, Brake - SOLVED

Recommended Posts

Hi team

Having a few off errors pop up on my OBC - 1994 E34. First of all - all lights/fogs/brakes are working perfectly.

When driving around with my lights off, nothing pops up. As soon as I turn my lights on I get the following errors:

DIP BEAM

TAIL LIGHT

LISC. PLATE LIGHT

and then as soon as I brake I also get:

BRAKE LIGHT

None of these show up unless the lights are on. So it has to be some weird wiring thing. I have read a few different explanations/fixes:

Rear boot wiring loom - Would this effect dip beam also?

Re-solder/replace LKM - Anyone done this?

Unplug headlight motors - Would this effect tail/lisc/brake lights?

Any ideas?

Thanks!

Edited by roo

Share this post


Link to post
Share on other sites

I get same, spasmodically depending on how she is feeling at the time. Like you Roo, all bulbs are fine, so I'm not going to chase it too much at this stage. When lights get turned on, its like it sorta does a 'self-check' on the system (note to self - must get around to reading owner's manual one day!!)

In terms of fault codes relating to lighting coming up on the OBC - my research seems to indicate if bulbs are ok, then highly likely 'fault code' is being tripped due to earthing gremlins within that circuitry.......

Mine passes wofs no hassles re lights, so its just another of her 'quirks' I reckon........

Share this post


Link to post
Share on other sites

It's a super annoying quirk though as I can't use the OBC for clock, fuel consumption, range etc while they are all showing up.

A lot of people put it down to headlight adjusters so will unplug those and see if it fixes it. Will also inspect boot hinge wiring tonight.

Share this post


Link to post
Share on other sites

Ditto - mines same while its 'self checking' or showing a fault or whatever - does yours not 'clear' after 30 secs or so, leaving OBC free for clock readings etc?? Took me ages before I learnt that OBC display can be replicated & shown in dash area itself too.......

Share this post


Link to post
Share on other sites

No it doesn't, not when the brake light one comes up. Obviously deems this is as more important than the clock etc which it is. Am aware I can have the same details showing next to the radio, would like both working properly though.

Share this post


Link to post
Share on other sites

Faulty CCM/ LKM

http://www.bmwe34.net/E34main/Maintenance/Electrical/LKM.htm

If you really want your OBC to work and not care about the check system remove the check module from the e-box under the bonnet, and you'll get a "check control" error every time you start the car instead.

Share this post


Link to post
Share on other sites

Seems like quite a common problem. People who have replaced the LKM actually had their lights stop working. Sounds like just the warnings could be wiring/headlight adjusters etc.

CCM is a good idea. Will ingestive these options tonight.

Share this post


Link to post
Share on other sites

also the headlight adjuster motors , fail and they cause alsorts of faults to come up , try unpluging them .

Share this post


Link to post
Share on other sites

brake light(or is it brake lt (elec) can be brake light switch,or maybe the centre hight stop light.

License plate can be the boot hing wiring

LKM resoldering is the fix for when you lights sometimes randomly dont work or go out

look here

http://www.bmwe34.net/

they all common E34 problems

can also get obc errors when using different brand bulbs and or one light is about to blow.I used to replace bulbs in pairs and keep the other one for a spare

Edited by kiwi535

Share this post


Link to post
Share on other sites

Update - Had a play after work. Loom going up the boot hinge had worn through its fabric sheath and could see the wires but none of the actual wires were exposed. I taped this up.

Headlight adjuster motors were a bit more tricky. I can't get either of the clips/plus off. They are really close to one of the bulb holders which makes it tricky (yes I was pushing the tabs out) and I didn't want to pull too hard as the motors don't look all the sturdy to be tugging off. Any tips for getting these plugs off?

Share this post


Link to post
Share on other sites

Bump, any more advice people? How can I correctly diagnose what is causing the problem? Is there a way to test the rear boot wiring? It's super annoying have this pop up every time the lights are on. All headlights and foglights are the same brand/type of bulb so it's nothing like that. Will try again to unplug the headlight adjusters but don't want to break 20 year old brittle plastic. Is there a way I can test the CCM?

Share this post


Link to post
Share on other sites

Can't really avoid breaking tabs as they are just too old I wouldn't as they plug in fine and are secure without them, you can always get new plugs if you wanted.

Easiest method is by swapping in a known good CCM and LKM modules

Share this post


Link to post
Share on other sites

unplug the head light adjusters , then see if the faults go away

9 times out of 10 they do .

Share this post


Link to post
Share on other sites

Finally got around to unplugging the headlight adjusters (after 3 lots of CRC and skinned knuckles) and no more errors! Thanks Brent & co.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

×
×
  • Create New...