I have a 2002 E320 4Matic. The "lamp malfunction" warning activated after applying the brakes. I checked the brake lights, the left side illuminates when the pedal is applied, but is not as bright as the right side. Bulb was changed, no difference, warning light continues to activate when brakes are applied. Any ideas?

 

Hi,
Possibly the connection between the bulb holder and the body of the light cluster. Remove the bulb holder and observe the two elctrical connections. Is the plastic adjacent to these melted. If so you have incurred a common MB problem with rear light units.
If this is the case you really need a new cluster.
However as a makeshift solution swap the Flasher and Brake light bulb holders after ensuring that any melted plastic has been removed so as to ensure the bulb holder fits the cluster freely. You also need to inspect the hole in the cluster since the heat generated by the poor connection can also melt the cluster body locally. The degree of melting is very small and local.
The melting occurs because the brake lights stay on for a long time when you are sat in traffic and have high wattage bulbs and the current causes heat at the connection between the bulb holder and cluster body. The flashers operate intermittently so don't have the same problem.
There is a recall for this problem in the USA on certain models including I believe the E series. I'm currently engaged in "dialogue" with MB over this issue since there is no such recall in Europe although the problem exists (common part and problem!)
Let us know how you get on.
Stuart

 

HI,

I had the same problem. After replacing the bulb holder/connector I still had the problem.
Finally sorted it out, bad quality bulb. Only use quality bulbs as the cheap ones risistance or something is not the same and the mercs electronics picks it up as a fault and isolates it.

Try this.

Johann