Tailgate Bulb Info

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SuffolkSifter

Active Member
Joined
Jul 9, 2020
Messages
98
Location
Ipswich, Suffolk
Car
ML350
Got a light out on my ML350 2012 - see picture (stock photo). No mention of this light or any listing of bulbs used in the Merc manual or on web. Are they to secret??

Can't see how to access the unit to see what bulb to get, could you help please?

Steve

ML Tailgate.jpeg
 
MB started using part-LED rear cluster lights from around 2010, though it was phased-in at different times for different models so not sure when the ML got them.

But it's very likely that the rear cluster is part-LED. Which light failed? Rear light or brake light?

If the failed light is LED, then the official solution from MB is to have the cluster replaced, though unofficially they can sometimes be repaired by soldering replacement LED.

Also, check all the electrical connectors for corrosion etc.
 
MB started using part-LED rear cluster lights from around 2010, though it was phased-in at different times for different models so not sure when the ML got them.

But it's very likely that the rear cluster is part-LED. Which light failed? Rear light or brake light?

If the failed light is LED, then the official solution from MB is to have the cluster replaced, though unofficially they can sometimes be repaired by soldering replacement LED.

Also, check all the electrical connectors for corrosion etc.
I have a similar question too about these rear light's. As I understand it ( and thats a bit of stretch of the imagination .. Veh electrics, and especially modern CANBUS systems are way outside my comfort zone....in spades !! ) when the parking lights are on, and you press the brake, it just "sends" additional current through the park circuit cables, causing the LEDS to brighten, which gives the brake light. OR are the park lights and brake lights on their own individual and independent circuits?
(Apologies SuffolkSifter for trespassing on your thread)
 
If they are the ones that brighten then they are on the same circuit.
For sidelights they are turned on and off very quickly with a short pulse. For brakelights the pulse is longer.
Known as Pulse Width Modulation 👍🏻👍🏻
 
So as someone who is not that good with electrics,I take it that this car has to have a new cluster at what £140 at least for a duff bulb/led,maybe we have somebody who can repair and give us a how to do it,could a auto electrician do it? :confused:
 
You need a new cluster......ask me how I know!
I have posted quite an extensive thread on this issue when I had the very same issue on my ML.

I will try and find it.
 
Here you go.....

 
Sorry to tell you but that tailgate cluster costs £235 plus fitting ! I thought they were bulbs... I can get a second user unit for £135, but would have to fit it myself (buy a pry tool for the panel clips), but not sure if there is a history of water ingress that causes the problem would be cost effective?

Thanks Abb for your link, no worries Justintyme trespass away.
 
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It just shows what a crazy car world we live in,well done Abbs for finding the fault shame it was not repairable,I see I was not far out with how much a new unit would cost,sometimes you feel we are going backwards when a bulb/led failure turns out to be a complete unit.
 
If they are the ones that brighten then they are on the same circuit.
For sidelights they are turned on and off very quickly with a short pulse. For brakelights the pulse is longer.
Known as Pulse Width Modulation 👍🏻👍🏻
In my previous 2010 E class w212, I used a universal relay to wire a car trailer to the car electrics. No problem's at all...worked like a dream. But now with my newer 2014 E class w212,, its problematic. Left / right turn, no problem. Brake light. no problem. But park lights? Yes, because in the 2010, brake /park were two different feed's and so no problem, but in the 2014 the brake / park are one and the same,,as you point out its the Pulse Width Modulation. BUT..one hope for a solution..if I take the trigger for the bypass relay from either the Nr plate light, or from the the same connection the SuffolkSifter is having the problem with? In his case, the brake light does not work in that cluster, only the park light, yes? I'm open to suggestions / comments / advice etc. I just need to get a constant park light feed to the relay for my trailer.
 
@Justintyme , that is exactly what I would do - take the sidelight trigger from the number plate light.
I would also take the brake light trigger from the third brake light as it is much less likely to be modulated than the brake lights (you can often see this flicker if you look out of the corner of your eye)
Can’t promise 100% that this will work as it’s 40 years since I was an auto electrician 👍🏻👍🏻👍🏻
 
Has anyone tried to claim this a a recall or failure? I have spoken to MB and they didn't say no and then asked which branch I would like to book in to. I have yet to get conformation from my local MB, but it's worth a try even if they won't do it FOC, maybe will put something towards it? After all they recognise it as a failure in manufacture and have made an improved unit to fix the issue.
 
@Justintyme , that is exactly what I would do - take the sidelight trigger from the number plate light.
I would also take the brake light trigger from the third brake light as it is much less likely to be modulated than the brake lights (you can often see this flicker if you look out of the corner of your eye)
Can’t promise 100% that this will work as it’s 40 years since I was an auto electrician 👍🏻👍🏻👍🏻
By the 3rd brake light, I take it you mean the rear window one??? And keep as far away as possible from the rear light clusters ? ( Indicator's being the exception ) Good Idea !!!
Don't worry too much about the 40 years since you worked as an Auto Electrician.....it like riding a bike, you never forget !!! and I would not be too far behind you since my mechanic days... and the innocence of electrics back then, when a BUS was public transport, and something anyone CAN use get from A to B, LOL. 😀
 
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Yes 👍🏻 The one in the rear window👍🏻👍🏻
 

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