W164 botched headlight wiring

[jimjohnstone]

Just bought 2006 ML350 about a month ago. Really unhappy with the dipped beams, and I've also had a dipped beam warning from day one, although the light is working.

The dips are halogen, but when I remove the bulb holder I found that the yellow wire had been removed completely and was just a loose end in the headlamp shell. There are 2 wires still attached to the bulb holder but one has been spliced (very poorly) to, I presume a live feed from somewhere else.

I'm thinking there is a fault further back in the system, and instead of fixing it properly, they have botched a fix around it.

Until I take the headlamp off I wont be able to check further, but does anyone have any idea where the problem might be if the yellow wire has been bypassed.

 

[jimjohnstone]

Bump. Anybody?

 

[Ted]

Couple of Qs
Doest the dip beam work on that side?
Is is as bright as the other side?
What caused you to take a look?

 

[jimjohnstone]

Dip works on that side, but I have a warning message on dash that it is not working ( I guess because the yellow wire has been bypassed). Don't think it's as bright but hard to tell, they are both pretty poor.

I was checking to see which type of bulb, as I need to fit better ones. Maybe Osram Nightbreakers or Philips Racing vision.

 

[Ted]

Pretty sure these are controlled from the front SAM, so looks like someone has run in a new wire - God inly knows where from, as you can't just take a tap from the other side.
I think you're just going to have to trace the new wire back and find where the other end is.

 

[jimjohnstone]

Thanks Ted. Hopefully I will know more once I remove the headlight. I'd really like to know what is the likely problem if they had to disconnect it from the SAM. Is it likely the SAM is faulty and how much to replace.

 

[Ted]

If it is the SAM my money would be on an output transistor failure - these are current limit protected rather than fuse. Best to find out what is going on first - there could be a perfectly logical reason for this such as additional driving lights or DRLs. Let us know what you find.

 

[jimjohnstone]

Handed the car back to the dealer and got my money back, also had balance shaft issues. Now bought an R320 CDI sport - with xenons.