W108 280SE - Trunk Light, LED

[Palolo]

My car came to me with the trunk light not working. In fact, since it didn't have a bulb in it, and I didn't know that the bulb sat *on* the switch (yeah, me = ) I puzzled over it for a bit.

Eventually, someone helped me figure out where the bulb went, and I was off to the races. I found a 5W bulb to put in and the circuit worked. However, it was a single bulb, and quite dim. I hesitate to put a higher wattage bulb in, for fear of melting the socket.

So I decided to order some "self adhesive strip LEDs" from here, to adhere inside the trunk lid and add more light. I also figure it adds a level of safety when along the road at night, but illuminating the trunk and me, if I am near that area. I didn't use the entire strip, saving a 7" section to use under the hood maybe, and a few other small strips to affix to door bottoms as puddle lights. (in case you are wondering, these are very low profile, and stick on with a 3M adhesive. very low power draw, cool to the touch, and flexible. Also, being mostly black, they are fairly discrete.

I ran the LEDs lead in to the switch, and trapped/affixed the positive lead between the positive terminal and the bulb base itself. The negative lead was grounded to one post of the trunk light switch. I will conceal the wires with a small piece of wire harness cover, and tape it to the lid for a better look.

Once it was all wired, I was impressed with the light output, color and even distribution.

I then closed the lid, and as I walked away, I asked myself "Hmmmm. I wonder why there was no bulb in the switch, given that it is easy to pop one in?" And I wondered if maybe it was taken out to "save the battery". So, I got down on the floor and put my eye up to the drain holes in the rear trunk tire wells. Sure enough: light is on!

My assumption was that the switch was not low enough, nor being turned off when the lid was closed. Fix: add a little rubber gubbins to the switch button, and now when lid is closed, the trunk light turns off. I bet the trunk light was draining the battery, so prior owner/mechanic just ditched the bulb rather than figure out why it wasn't working right and fix it...

No Benzes were hurt or mutilated in this project, and all of the above is reversible (not that you want to put the trunk lights on the outside...)


Pic 1: trunk light switch
Pic 2: "before" - kinda dim
Pic 3: "after" - LEDs kick in
Pic 4: Looking up at the strip