Free power...headlamp.. ;)

[Dieselman]

I have always thought the standard H7 headlamps on my car were poor with a yellow light and undefined cut-off.
Today whilst doing another job I decided to measure the headlamp supply voltage and found it about 1.2v below battery voltage. I tested with a wire straight to the main battery terminal and the light became noticeably brighter and whiter, even in todays full sunshine.

This made me think of adding additional relays and heavier cabling to supply battery voltage, but before making any changes I had a look at the wiring harness leading to each lamp unit.

Tracing back from the lamp connector I found an identical connector and fly-lead to supply the lamps.I suspect this is for ease of installing different lamp types at production.

Reaching down to get the connector so as to meter for voltage drop I found it to be hot...in fact hot enough to have cracked the casing..
This indicated a resistance so I looked at the connector and found it is a replication of the lamp connector, so I unplugged the fly-lead and plugged the main loom into the lamps.
This has resulted in brighter and whiter lamps with a more defined cut-off..

The reduction of voltage against battery voltage, with only dipped beam on is now only 0.5v.

The best bit is this is a free mod.

If I find the lamps are still not good enough I will add relays and better wiring, as with more lights on, such as main beam, there was a voltage drop still evident.

 

[whitenemesis]

Interesting.

I have never noticed this yellow headlamp on other Es..

If the extra connector is identical how does this facilitate fitting different types?

 

[Dieselman]

Interesting.

I have never noticed this yellow headlamp on other Es..

If the extra connector is identical how does this facilitate fitting different types?

Presumably the fly lead has different connectors on the headlamp end.

All halogen E's, both W210 and W211 have poor headlights. There have been a number of complaints on here.

They don't appear especially yellow..until full voltage is applied..then they appear much whiter.

The wiring and connectors are 'marginal'....

 

[whitenemesis]

Could this be anything to do with "Daytime" running lamps?. Depending on the spec these run at reduced voltage

 

[Dieselman]

No. The harness is simply a pass through. If for example the car had Xenon lights, the same main loom could be used but with a different interconnecting loom going to the ballast instead of the light unit itself.

The two pictures depict the lamps on dipped beam against side lamps and main beam, simply to show how white they now appear, they are not before and after pics.

They used to appear slightly more yellow.

This has also got me thinking about if people want to run LED or Xenon lamps without having bulb warning messages.
They could wire a relay in to switch the power to the lamp and allow the bulb warning circuit see the relay as the load.

 

[timskemp]

Just stick an aftermarket HID kit in it...



[waits]

 

[Dieselman]

Just stick an aftermarket HID kit in it...



[waits]

Ha ha..LOL.....

One thing to notice though is the clearly defined beam from the lights. There is no 'Halo' even with a picture taken straight on....

 

[Howard]

Nee Naw Nee Naw ...... the xenon police are on their way !!

 

[Diesel Benz]

Nee Naw Nee Naw ...... the xenon police are on their way !!

Crap Chinese HID kits are becoming so popular that the Police is starting to look after these cars at our place already. These kits may give improved light density but the pattern may not be good at all even for the driver and it is usually pretty bad for oncoming traffic.

MB halogen lights are often blamed to be poor, even when compared with other cars with halogen lights. I'm not sure how true this is but it almost feels like MB pushes owners to spend their money on Xenons which aren't exactly cheap.

Considering the original topic, I'm afraid that the voltage loss at wiring has been taken into account at the factory. The halogen bulbs life is likely going to be a lot shorter after the voltage increase from improved wiring (if it only came from the wires, not from improved or corroded connectors). Could still be an acceptable compromise.

 

[timskemp]

Joking aside - I'd have been happy with the halogens if they'd had the beam spread and coverage of our volvo, but like Dieselman I thought they were poor even on the W212.

 

[Diesel Benz]

Joking aside - I'd have been happy with the halogens if they'd had the beam spread and coverage of our volvo, but like Dieselman I thought they were poor even on the W212.

I did not get the joke, unless you mean "MB halogen lights". Some car magazines rate the 212 halogens low. But I don't see why 212 would be better or why 211 or 210 should not be as good as other car brands with halogen lights. We've had several Volvo's in the family in the past and their halogen lights were really good.

 

[stevesey]

I did not get the joke...

Linky (re: Xenon Police) a hotly discussed subject.

 

[Dieselman]

MB halogen lights are often blamed to be poor, even when compared with other cars with halogen lights. I'm not sure how true this is but it almost feels like MB pushes owners to spend their money on Xenons which aren't exactly cheap.

I've long suspected that to be the reason for poor Halogen lights on MB cars.

Considering the original topic, I'm afraid that the voltage loss at wiring has been taken into account at the factory. The halogen bulbs life is likely going to be a lot shorter after the voltage increase from improved wiring (if it only came from the wires, not from improved or corroded connectors). Could still be an acceptable compromise.

I understand what you are saying but don't think it is the reason for two reasons. No1. I measured our 'other' car and found the voltage to be 1 volt higher at the lamp terminals and hasn't had any headlamp bulbs blow in five years, and 2. MB for the lowest grade wire they can get away with which causes losses on both feed and earth wires. The loss reduces the voltage when more lights are switched on, which even if they had decided to run with a set maximum voltage then the loss reduces this when on high beam.

I can't see MB electrical designers specifying additional looms where the connectors get hot.

 

[Dieselman]

I have noticed my headlamps getting more discoloured due to the lacquer aging and going off colour, which I was sure was affecting light output and beam definition, so having been meaning to do this for ages, today I got round to giving the lenses a strip and polish.


Before picture.

First I wet sanded the lacquer off using 600 grit paper, followed by 1200 grit, then fine sanded with 2000 grit.

After sanding the lights looked like this. You know when the lacquer is all off because when sanding it, there is a milky, foamy residue.

I then got out the rotary polisher and using regular fine car polish and two passes got results like this.

Was the end result worth the effort and considerable pain it has given me.


The light beam on a wall now looks well defined and bright.

And on a dark lane gives a great spread of light on dip beam.

I really can't see the need for upgrading the lights now they are back to a decent level of performance.

I can see there is some dust being illuminated inside the light units so will strip and clean them sometime as I have seen a marked improvement on one of my other cars from doing just that.
I have two identical cars, both of which had poor lights but after cleaning the worst ones they are now good and the other ones are poor, so cleaning does make quite a difference.

Also, I might install better wiring than Mercedes fitted to stop the voltage drop dimming the lamps.

 

[ALNoteman]

Lights wiring

Hi Diesel Man,

All interesting and useful stuff. Having sailed and live on boats for year I know w little bit about electrical wiring in damp environments. Before we left Cape Town for the UK I made sure that the cables I used for the masthead lights was of a thickness a little larger than needed (2.5-mm) I made sure that it was tinned copper and I specified the insulation as Teflon to resist chaff. In 16000-miles we never had a masthead light failure. Untinned cables tend to corrode very soon as soon as there is any dampness.
Al.

 

[Simzy]

I have noticed my headlamps getting more discoloured due to the lacquer aging and going off colour, which I was sure was affecting light output and beam definition, so having been meaning to do this for ages, today I got round to giving the lenses a strip and polish.


Before picture.

First I wet sanded the lacquer off using 600 grit paper, followed by 1200 grit, then fine sanded with 2000 grit.

After sanding the lights looked like this. You know when the lacquer is all off because when sanding it, there is a milky, foamy residue.

I then got out the rotary polisher and using regular fine car polish and two passes got results like this.

Was the end result worth the effort and considerable pain it has given me.


The light beam on a wall now looks well defined and bright.

And on a dark lane gives a great spread of light on dip beam.

I really can't see the need for upgrading the lights now they are back to a decent level of performance.

I can see there is some dust being illuminated inside the light units so will strip and clean them sometime as I have seen a marked improvement on one of my other cars from doing just that.
I have two identical cars, both of which had poor lights but after cleaning the worst ones they are now good and the other ones are poor, so cleaning does make quite a difference.

Also, I might install better wiring than Mercedes fitted to stop the voltage drop dimming the lamps.

Did the lights stay like this ?? Also what polish did u use as they look sick ..

 

[Dieselman]

They are still fine. I used regular car polish, not wax, just polish.

 

[Simzy]

They are still fine. I used regular car polish, not wax, just polish.

Thank im gunna have a crack at mine again ..just cant seem to get em like yours though

 

[Dieselman]

The worse they look at stage 2, the better they will be at stage 3.

 

[Simzy]

The worse they look at stage 2, the better they will be at stage 3.

And you didnt spray any clear coat on the light afterward to seal it ??