Hella headlights

Post here for mechanical and engine topics such as fuel issues, transmission problems, rough idle, exhaust, electrical issues, etc

Moderators: GRNSHRK, ron, bfons

Post Reply
635Convert
Posts: 14
Joined: Tue Jul 14, 2015 4:34 pm
Location: England

Hella headlights

Post by 635Convert »

I have just had a fail on MOT citing the headlamp not working on dipped beam. I have dismantled and cleaned it and is does actually work but strangely it seems to be a weaker light that the drivers side and am concerned that when i go back for a retest i will be told it is not powerful enough.
The outside of the lens whilst a bit scratched is still OK and I have cleaned up the inside of the unit as well but it does not shine as brightly as the drivers side.
I cannot understand why it would not be as powerful as I have also replaced both sides with new bulbs.

If I have to buy a new/used unit and as mine incorporates the sidelight as well, there does not seem to be any on the market in the UK.
Did the E24 share the same headlight ( i.e. incorporating the sidelight) as any other BMW which might make my search easier??
Just to clarify the unit has a sidelight built into the top and also has a large (magnifying) lens inside as well. Ellipsoid???

Any help greatly appreciated
User avatar
raykoke
Posts: 121
Joined: Sun Mar 02, 2014 11:18 am
Location: Savannah GA USA

Re: Hella headlights

Post by raykoke »

I'd poke around at the grounds and see if a poor ground may be the issue.

Good luck,

Ray
'85 ///M635
baders
Platinum Member
Platinum Member
Posts: 1084
Joined: Sun Nov 23, 2014 7:38 am
Location: Perth Australia

Re: Hella headlights

Post by baders »

It would help if you put your car details in your signature.

For my RHD right side driving country/car, I went to Genuine Parts GmbH;

https://www.originparts.de/

Not cheap, but they had OEM headlights in stock.

You might also want to get a multimeter and check the voltage at the headlights. You may have a wiring problem.
1986 635csi LOCUTUS / Arktis Blau Metallic / Pearl Beige / S38B36/ Close ratio dogleg 5sp
2002 E46 M3 / Topaz Blau Metallic / Black Nappa / 6 speed SMG software tuned / Bilstein PSS10 Coilovers / CMP RACP reinforcement
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Hella headlights

Post by dwcains »

As the other two members have postulated, I also think the problem is not in the headlight itself. Measure the voltage across the bulb terminals and compare to the other side, but it should certainly be >12.5V with the engine running. If not, look for the ground wire(s) on that side and make sure the connections are clean and tight. If the problem remains, start tracing back the power lead and check the fuse connection.
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
635Convert
Posts: 14
Joined: Tue Jul 14, 2015 4:34 pm
Location: England

Re: Hella headlights

Post by 635Convert »

Thanks for the input. The car is an 88 manual 635 which whilst has had a lot of money spent on it still needs detailing and sorting under the bonnet.Will investigate the earthing over the weekend to see if that is the problem, have als ordered a lightbulb HID upgrade as well to see if that helps.
Will post outcome next week as to results.
Thanks for the help
User avatar
raykoke
Posts: 121
Joined: Sun Mar 02, 2014 11:18 am
Location: Savannah GA USA

Re: Hella headlights

Post by raykoke »

Cool!

Are HID conversions legal there?

Daniel Stern has an opinion about most kits...

https://www.danielsternlighting.com/tec ... sions.html

He suggested to me once when I was considering LED heradlamps, that Philips LED bulbs might be satisfactory. But I didn't pursue.

Cheers,

Ray
'85 ///M635
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Hella headlights

Post by dwcains »

I've never been a fan of the HID conversions, as they compromise the beam pattern and tend to shoot a lot of glare at oncoming drivers. Proper halogen bulbs should be more than sufficient in the original lamps, and if you can get the equivalent HIR bulbs, you'll have the best possible setup.
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
baders
Platinum Member
Platinum Member
Posts: 1084
Joined: Sun Nov 23, 2014 7:38 am
Location: Perth Australia

Re: Hella headlights

Post by baders »

635Convert wrote:Thanks for the input. The car is an 88 manual 635 which whilst has had a lot of money spent on it still needs detailing and sorting under the bonnet.Will investigate the earthing over the weekend to see if that is the problem, have als ordered a lightbulb HID upgrade as well to see if that helps.
Will post outcome next week as to results.
Thanks for the help
I'm always very cautious when it comes to headlights here. There are strict rules (Australian Design Rules) which govern what you can and can't do with car lighting. I imagine the UK would be the same. How will the car go when MOT time comes ? Is that something they check at MOT ?
1986 635csi LOCUTUS / Arktis Blau Metallic / Pearl Beige / S38B36/ Close ratio dogleg 5sp
2002 E46 M3 / Topaz Blau Metallic / Black Nappa / 6 speed SMG software tuned / Bilstein PSS10 Coilovers / CMP RACP reinforcement
Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Re: Hella headlights

Post by Jambers »

Hi, just searching and came across this old post about a dim headlamp on a Highline 635CSi here in the UK. I have the exact problem but on the drivers side.

The multimeter shows identical power to both sides of the car at the bulb connectors so I have narrowed it down to the lamp unit itself. I have changed bulbs etc and to no avail.

Did you ever manage to sort it? Thanks, really appreciate your feedback.
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
User avatar
hornhospital
Platinum Member
Platinum Member
Posts: 2931
Joined: Sun Jul 11, 2010 6:46 pm
Location: Silverhill, AL
Contact:

Re: Hella headlights

Post by hornhospital »

It's the ground ("earth") for that light, not the power.
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Re: Hella headlights

Post by Jambers »

Thanks - will take a look. Interestingly the drivers side is really quite dirty in there, whereas the passenger side is pretty clean, no doubt due to the air intake.

It could well be a dodgy earth, will have a go at it this weekend.
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
User avatar
86_6series
Platinum Member
Platinum Member
Posts: 1069
Joined: Mon Apr 02, 2007 10:08 pm
Location: West Nyack, NY

Re: Hella headlights

Post by 86_6series »

Before you check the ground on your harness, I would bypass the connection and use good wires and
feed hot and ground to bulb to see if it's brighter. If the bulb did get brighter I would use one wire at a time as jumpers.
One connected to hot harness to bulb with ground jumper from bulb to good ground. If the bulb is not bright it's the hot.
Switch harness ground to bulb and hot direct to bulb, if not bright, it's the ground. Easy quick check to isolate problem area.
Now if the bulb is bright with both tests----I don't have an answer.

Just my $.02
86-635CSi
96-MB C220 SOLD
98-740i
71-Continental MK3
Jambers
Posts: 62
Joined: Mon Aug 28, 2017 9:41 pm
Location: East Midlands UK

Re: Hella headlights

Post by Jambers »

So I have now finally done this, using jumper wires to bypass everything, right back to the battery, and still it is dim. I'm now thinking I need a new headlight.I think it might be a corroded reflector or something.

I have been reading on here, and whilst I know that there are no other headlights that can be slotted straight in from another BMW model, is it possible to get an e30, e32, or e34 ellipsoidal and take all of the insides out to swop over, retaining the lens/mounts from the existing lights so I can still mount it back in?
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
Platinum Member
Platinum Member
Posts: 4569
Joined: Sat Jul 10, 2004 11:35 am
Location: South Wales U.K.

Re: Hella headlights

Post by ron »

Post a pic of the headlight front and back. I may have a spare.
They are ALWAYS rustier than you thought!!!!!!
'85 M #228
'87 M #367
'88 High line.
'10 X5
‘84 Alfasud 1.5 ti
ron
Platinum Member
Platinum Member
Posts: 4569
Joined: Sat Jul 10, 2004 11:35 am
Location: South Wales U.K.

Re: Hella headlights

Post by ron »

Still waiting for your pic!!
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: Hella headlights

Post by Jambers »

Hi Ron, sorry about that. These are best pics I can get. Its the Hella one, drivers (right hand) side


https://photos.app.goo.gl/ugDou1HWNDuQhnDi8
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
Post Reply