W211 Xenon Headlight faliure

[Chattonmill]

Typical.
Warranty runs out and 5 days later so does the headlight!
£92 for a new bulb! Turns out it isnt that and Merc need it back in for a diagnostic at £75! (Altough they may be able to get goodwill on this)
So if it is not the bulb, would anyone have any ideas what it might be

 

[PJayUK]

Bulb control unit or Ballast?

 

[Chattonmill]

Is there any way of checking these apart from at a dealer?

 

[Baron_Samedi]

Ballasts generate stupid amounts of voltage which would make me shy away from messing with the outputs.

But... getting a spare ballast with output connector for the bulb (sic) would be a bigger pain in the rump than giving the car to someone with STAR etc for a diagnostic.

 

[PJayUK]

Very low current though, unless you have a pacemaker fitted then there's not much risk. Having said that its not a very pleasant experience!

The OP could try swapping the bulbs over to see if the issue moves from one side to the other. Other than that the best option is to let a dealer or indi have a look.

 

[Dieselman]

Can't the ballast be swapped side to side to test.?

 

[Baron_Samedi]

Aren't the ballasts attached to the headlamp cluster?

Oh and high voltage can kill you as easily as current.... bit of a mis-conception I'm afraid.

 

[Dieselman]

You need a minimum of both for death of an average person.

That's why a static shock or Van de Graaff generator doesn't kill you. Walking over synthetic carpet can give you a 25Kv static belt, not seen anyone die from that yet.

 

[vijilants]

If the ballasts are external to the unit, yes they can be swapped from side to side.

Depending on the vehicle, you may have a situaltion where the external ballast unit connects to the headlamp and within the headlamp you have an ignightor that connects to the ballast and the other end ofthe ignitor connects to the bulb.

If you find that the ballast is faulty and you can get the bosch number from it, go to a bosch agent. The price is 25% of the same unit from MB.

 

[Adam230K]

Have both your bulbs failed? If not, swap the working bulb to the other side and see if it works, if it does then your ballast is fine, buy a new bulb from Halfrauds for 20 quid. If not then your ballast is buggered and you should get an exact replacement for continuity.

 

[Chattonmill]

Merc had a look at it briefly and said that the bulb itself was fine, so that would leave the ballast and the igniter as possible problems I assume.

 

[PJayUK]

Not sure if it helps much, but this is what WIS says on the subject. Its for a 220 but the principles are much the same

PM me if you want a "proper" .PDF with pics with your email addy!

AR82.10-P-4632N Removing and installing xenon headlamp control module 29.4.99 Removing and installing xenon headlamp control module 29.4.99
MODEL 215, 220 with CODE (612b) Xenon headlamp unit
Illustrated on model 215

1 Screws
2 Mount
E1n1 Xenon headlamp control module
E2n1 Xenon headlamp control module

P82.10-2426-06 Removing, installing

Danger! Contact with components under high voltage
can pose lethal hazard
Do not touch parts under high voltage. Persons
with electronic implants
(e.g. pacemakers) should not perform work on
ignition system.
AS15.10-Z-0001-01A
a
Danger!
1
Danger! High voltage from xenon headlamps
Removing and installing headlamp unit
Do not touch parts under high voltage. Persons
with electronic implants
(e.g. pacemakers) should never work on xenon
headlamps.
Model 215
Model 220
AS82.10-Z-0001-01A
AR82.10-P-4730N
AR82.10-P-4730MA
2 Unscrew screws (1) and remove mount (2)
3 Disconnect xenon headlamp control module
(E1n1, E2n1) from headlamp
4 Install in the reverse order
5 Check for proper function

Copyright DaimlerChrysler AG 17.03.2009 CD-Ausgabe G/09/05 . This WIS print-out will not be recorded by Modification services. Page 1

 

[Chattonmill]

I may just wait for the dealer as They have said that Goodwill will probably cover it, If I fiddle about and break something then it definately wont!

 

[Bobby Dazzler]

I had the ignitor/bulb and ballast replaced. In the end it was the headlamp itself. All under warranty though.

MB used to recommend changing both "bulbs" at the same time to ensure colour match, but don't actually do that in the event of a warranty or goodwill repair.