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Puddle lights not turning off!

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Hi guys hope all is well.

I swapped out my puddle lights a few months ago with osram LEDs. No issues.

Today I noticed that the puddle lights don't switch off entirely. You can see them dimming but not switching off completely.

The only thing I did recently was remove the drivers door card to check a rattle. I made sure I connected everything back up properly.

Any ideas please? 

Cheers all 

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LED’s ( cheaper ones at least) can be quite troublesome, and the fact that automotive circuitry can be non-conventional shall we say doesn’t help! For example a lot of circuits on vehicles do not ‘switch’ the ‘live’ conductor going to the load ( as in most electrical circuitry) but in order to save on cable the return is in fact the metallic structure of the vehicle, so this means the load is constantly powered.

Recently had some problem with household LED’s in a timer controlled outside light fitting whereby the light never actually went completely off! Turns out the timer ( which included a photocell) had a minimum load spec and this was the problem.

I have fitted LED’s throughout the interior of my 250 and all seems to function ok!

paul m

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The puddle lights are not controlled by a conventional switch, but by a transistor being turned on, and off slowly. The load governing the rate of turn off. With small loads "as with small LED bulbs" this can cause the transistor to pass a small leakage current as it does not fully turn off.  LED's only require a very small current to remain alight. A 30 ohm 5 or 10 watt resistor wired in parallel with the LED should cure the problem, but is wasteful on energy in effect loading the circuit to the same level as the OEM bulb. For puddle lights this is not rely an issue as they normally do not stay on for long periods.


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