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Discussion Starter #1
So I finally got around to fixing the soft close problem on my wife's s55 and thought I'd fix the inside handle illumination I just happened to have 8 blue 12 volt chip LEDs left over from another project so I proceeded to replace the bad led with the upgrade and wow pretty cool so I did the other three doors. Then i did all 4 doors on my s55. Now here's the problem only the front two doors on wifes 2005 s55 work, none of them work on my car and back doors on hers I verified the polarity on the new LEDs and tested all the old leds which all were bad. I looked in all the modules for coding, I can't locate any switching circuits. I assume they are powered from their respective door control modules so what are the chances all these modules are bad and only the door handle illumination circuit. What am I missing?
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Discussion Starter #3
They seem to be working correctly on front doors only on one out of two cars I did repair on . I should add that they are always on with key on and shut off a few minutes after key removed. I guess that's how they are supposed to work. Does anyone have working handle lights to confirm proper operation
 

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Discussion Starter #4
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Brighter in the picture than reality probably an exposure setting in phone camera. But it comes on when key in position 1 and turns off after a few minutes upon removing key. Dosent seem to be affected by light sensor and only front two doors work. And none work on other s55 and also have a s430 that has original leds and only 88000 miles and they're dead also. Did any of these ever work? I know it's an insignificant feature on these cars but if it's there it should work, or at least be repairable. I live for these kinds of challenges, story of my life, fixing broke things. If the dcms driver circuit is bad then what are the odds I got two good ones on 1 car in front doors only. I never have that kinda luck, usually much worse.
 

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On my 2004 S500 all four work (still the originals). On my 2004 S350 all work (although the rear right was bad and I replaced it with similar size LED diode).
You can swap DCMs between cars to debug. Either your new LEDs are drawing too much current and DCM has disconnected them (the front ones on your car work only by luck due to some peculiarities of resistance), or these 6 DCMs have these ports damaged (for some reason).
 

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Hi,

/\ /\ /\ Agreed with @Pokseva ...............

I have 2 W220's all work on both cars, I think that the DCM is switching them off for one of 2 reasons .................

Polarity is wrong, current draw too high (or maybe too low) 😉

HTH,
 

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Discussion Starter #7
I'm noticing that the light on the underside of outside mirrors is never on. What conditions would it normally illuminate? Seems I remember seeing it on recently on wifes s55. Maybe it's related to my inside illumination problem, isn't it also powered by dcm.
 

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Door Opened in the dark.

Yes it is powered via DCM, but reliant on the Auto Lighting Daylight Sensor ;)
 
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