2011 w204 C class double flashing indicator

[nasifkhan]

Hi all, 1st time poster so please bare with me.

I acquired my 1st Mercedes in September 2019 and absolutely love everything about it.

I have the intelligent light system on my C220 CDI. The issue I'm having is that the OSF indicator double flashes when indicating right. On the dash it says 'check turn signal' or something like that and it clicks fast.

The rear turn signal and the mirror turn light are both flashing at the normal pace.

I have also noticed that the 'C' shaped LED/Strobe light is also flickering.

I have checked fuses and wires and all seems to be ok.

I have a video of it...

Any ideas what to do next?

 

[Arv]

It could be that wrong light bulb is installed. Indicator clicking interval is somewhat sensitive to the electrical circuit impedence. May try changing the light bulb if you would like.

 

[nasifkhan]

Is there any way of checking the control unit?
I suspect this is at fault as all bulbs and LEDs are working.

 

[Uncle Benz]

I would try replacing the bulb first. Sometimes they appear to be working fine, but when you take the bulb out it looks very black. The system is very sensitive to dodgy bulbs. Failing that have a look at the multiplug that goes onto the lamp unit for blackening or burning of the earth pin

 

[nasifkhan]

To get to the plug, do I have to take the headlight out?

 

[Uncle Benz]

No

 

[umblecumbuz]

One indicator only playing up as you've described often suggests a dodgy earth to the bulb.

 

[nasifkhan]

RESOLVED - for anyone who has this issue, I changed the black LED/DRL control module and it works fine now.

Problem was that some water had got into the module connection.

Had to remove part of the bumper to get headlight out. Swapped the control module, no coding required in my case.