Strange headlamp behaviour

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Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Strange headlamp behaviour

Post by Jambers »

Strange thing happened. Today was driving for the first time after a few weeks and the gong sounded, check warning on the Dash, and "Dipped Headlamp" warning illuminated on check control. Any way got back home and have discovered the following:

Switch off everything, switch off car. Switch back on. No warnings.

Put parking lights on. Come on as usual, all OK, no warning on Check control

Then headlamps on, and check control comes on with "Dipped Headlamp" warning on check control. Both headlamps are on.

Then back to Parking lights on, and the left hand side (nearside in UK) headlamp stays on, at what looks like half power.

Headlights on - all OK but that same headlamp seems brighter.

Was going to replace the bulbs, but anyone have a clue as to what might be happening? Any help would be appreciated. Car is in for MOT on Friday, this is all I need ](*,)

As per signature - car is a High Line with Ellipsoids
Current cars:
1989 635CSi Manual
2007 Z4M Coupe
G31 530d M Sport
F21 118i M Sport
Based in the U.K. Leicestershire
Previously : F30, E60, E21, E30, E12, E28
ron
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Re: Strange headlamp behaviour

Post by ron »

Check control light coming on when switching on headlights is very common. Could try cleaning all the bulb contacts and in the boot on the rear wall is the relay box. Try pulling the plug and squirt some contact cleaner into it and the socket on the box.

These might explain the low power headlights.

viewtopic.php?f=2&t=15498&p=110277&hili ... ht#p110277

viewtopic.php?f=2&t=4743&p=31804&hilit= ... ght#p31804

viewtopic.php?f=2&t=24205&p=171475&hili ... ht#p171475
They are ALWAYS rustier than you thought!!!!!!
'85 M #228
'87 M #367
'88 High line.
'10 X5
‘84 Alfasud 1.5 ti
Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Re: Strange headlamp behaviour

Post by Jambers »

Wow, Ron - thank you so much for this! Gives me something to do!! Once again, many thanks - really appreciated.
Current cars:
1989 635CSi Manual
2007 Z4M Coupe
G31 530d M Sport
F21 118i M Sport
Based in the U.K. Leicestershire
Previously : F30, E60, E21, E30, E12, E28
Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Re: Strange headlamp behaviour

Post by Jambers »

Well, just been out to it and just gave the RH lamp a nudge and the headlight on that side came on, so I think it is a dodgy bulb on the drivers side. It looks like a pig to get to as the huge washer bottle is in the way. Had a quick look at the washer bottle and it only lifts just clear of the chamfered bracket, then it has the pump connections etc.

Car is in for an MOT on Friday and I might just ask the INDY to sort it out. Got some H1 bulb, and have replaced the passenger side - I'll let the garage sort the drivers side.
Current cars:
1989 635CSi Manual
2007 Z4M Coupe
G31 530d M Sport
F21 118i M Sport
Based in the U.K. Leicestershire
Previously : F30, E60, E21, E30, E12, E28
GRNSHRK Online
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Re: Strange headlamp behaviour

Post by GRNSHRK »

Jambers, moving your thread to the "electrical" section, surprised that Ron didn't do this for you :-k
:mrgreen:
Bobbo
1980 633 CSi Cypress Green/Pearl Beige
2017 X5 M Sport Xdrive 35i Carbon Black/Ivory White
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ron
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Re: Strange headlamp behaviour

Post by ron »

GRNSHRK wrote: Mon Apr 02, 2018 6:18 pm Jambers, moving your thread to the "electrical" section, surprised that Ron didn't do this for you :-k
Oversight on my part, Bobbo. ](*,)
They are ALWAYS rustier than you thought!!!!!!
'85 M #228
'87 M #367
'88 High line.
'10 X5
‘84 Alfasud 1.5 ti
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Brucey
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Re: Strange headlamp behaviour

Post by Brucey »

your car is probably fitted with 'dim dip' headlights. When the engine is running the sidelights include the dipped beam lights, on half power courtesy of a ballast resistor in series with the bulbs at this stage.

If it isn't just a bad connection it sounds like one of the ballast resistors has perhaps gone open circuit. Not sure if it is any longer a requirement to have the dim-dip headlights working for the MOT; they were only fitted to UK cars for a few years.

Getting at the headlights isn't too bad; just be sure to familiarise yourself with how H1 bulbs are clipped in first. Also the cover over the back of each housing is on a bayonet; IIRC you turn the cover ACW (as you look at the back of the light) a short way and then the cover comes off.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Re: Strange headlamp behaviour

Post by Jambers »

Thanks Guys - couldn't decide if it was electrical or just workshop - but the clue I suppose is in the fact that the headlights are electrical! Doh!

Anyway, it's my fat fingers and whether or not I can get them behind the massive washer bottle. Will have a another crack at it. It's going in for MOT on Friday. I think the coolant needs bleeding too as the temp needle sways about a bit between left o centre and right of centre. When it was restored the garage took the rads out and probably didn't bleed it.

Thanks - I'm going to use a garage called MSC in Leicester, the chaps there worked for John Hurst who was well known as a BMW specialist in Leicester, so hopefully it's in good hands.
Current cars:
1989 635CSi Manual
2007 Z4M Coupe
G31 530d M Sport
F21 118i M Sport
Based in the U.K. Leicestershire
Previously : F30, E60, E21, E30, E12, E28
Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Re: Strange headlamp behaviour

Post by Jambers »

OK - so changing the bulb was the easy part - just removed the Air Filter housing (3 bolts into the bracket and the jubilee for the hose towards the Intake/engine). Took no more than 3 minutes.

Looks like I have some electrical gremlins, in the wires. That bulb still looks as though it is only running at half wick even with the engine on.

The bulb itself was fine but I changed it anyway. just small movements on the wiring loom is causing the bulb to go out, and when it is on it is at half mast!

So it needs time and effort to take all the tape off and work out whether or not there is a cracked wire or something else going on. It's not where the bulb sites - that is all clean and the bulb is nice and tight without any "play" in its seat.

The wiring loom does look old (which it is of course) - has anyone ever replaced sections of it, and if so how easy - sorry - how difficult - was it?
Current cars:
1989 635CSi Manual
2007 Z4M Coupe
G31 530d M Sport
F21 118i M Sport
Based in the U.K. Leicestershire
Previously : F30, E60, E21, E30, E12, E28
Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Re: Strange headlamp behaviour

Post by Jambers »

The yellow connector on the back of the light housing was at fault. The garage have managed to remove it and cable tie the wires firmly which has stopped the issue.

So I'll be the hunt for new clips. I need to source them on RealOEM!
Current cars:
1989 635CSi Manual
2007 Z4M Coupe
G31 530d M Sport
F21 118i M Sport
Based in the U.K. Leicestershire
Previously : F30, E60, E21, E30, E12, E28
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nick88highline
Posts: 348
Joined: Fri Feb 06, 2009 11:31 am
Location: Suffolk, UK

Re: Strange headlamp behaviour

Post by nick88highline »

Here are the seven digit BMW part numbers for the front light connectors:
High Beam: 1378401
Main Beam: 1378403 (yellow)
Side and Fog: 1378402

I replaced mine a few years ago as the connectors tend to crack at the cover hinge.
My car is a Highline (1988), so these part numbers may not be correct for pre 6/87 models.
Nick
BMW 635CSiA (1988)
BMW i3 (2016)
Jeep Grand Cherokee V8 (2000)
Morris Minor 1000 (1968)
Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Re: Strange headlamp behaviour

Post by Jambers »

Thanks for the replies - does anyone know how to bypass the "Dim-Dip feature" on a highland in the UK? I thought I saw some details but cannot find them on here now.
Current cars:
1989 635CSi Manual
2007 Z4M Coupe
G31 530d M Sport
F21 118i M Sport
Based in the U.K. Leicestershire
Previously : F30, E60, E21, E30, E12, E28
ron
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Posts: 4569
Joined: Sat Jul 10, 2004 11:35 am
Location: South Wales U.K.

Re: Strange headlamp behaviour

Post by ron »

Jambers wrote: Mon Apr 23, 2018 7:56 am Thanks for the replies - does anyone know how to bypass the "Dim-Dip feature" on a highland in the UK? I thought I saw some details but cannot find them on here now.
Highline sidelights
Post by ron » Fri Jun 15, 2007 11:31 am

If you don't want the half-power sidelight feature just disconnect both

plugs on the resistors loom.The resistors are mounted behind the L/H

headlight unit (2 white barrels clamped together held on with 2 bolts)

just forward of the battery.


I had to disconnect mine as the HID units objected to half voltage!!!

HTH Ron.
They are ALWAYS rustier than you thought!!!!!!
'85 M #228
'87 M #367
'88 High line.
'10 X5
‘84 Alfasud 1.5 ti
Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Re: Strange headlamp behaviour

Post by Jambers »

Thanks Ron, as ever you are a star!
Current cars:
1989 635CSi Manual
2007 Z4M Coupe
G31 530d M Sport
F21 118i M Sport
Based in the U.K. Leicestershire
Previously : F30, E60, E21, E30, E12, E28
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