kikicoco1334

Hi I have a 2005 w203 C320 4Matic its front driver side turn signal just stays on even when I turn the car off and take out the key. On the screen it indicates the turn signal bulb needs to be replaced.

I've done so far:

1. changed out the bulb - no change
2. tried the bulb screw on housing from the right side - no change
3. plugging the bulb and the screw socket to the right hand side - the socket and bulb works
4. checking the relay - it states "Headlamp flasher (i assume its the blinker) - electronic" I am not sure what that means... is it controlled by computers or just a relay?
5. I saw this "Light activation is by the SAM's themselves when they receive a signal on the CANBUS. They are electronically protected - no fuses." does that mean my SAM's having issues?


I've also checked link below and my fuse box looks nothing like it
http://www.mercedes.gen.in/mercedes-...ndicator-cure/

and here is the diagram of all the fuse boxes:
http://www.mercedesmedic.com/2001-20...gram-pictures/

Any help is appreciated.

LexBrett2

Sounds like a defective relay? Have you swapped out the relay for another relay? It is worth a shot, pretty sure turn signals function from a relay. The electronic device stays in last position when the relay fails I believe.

Also do you have a icarsoft mbII reader? Might give you more info to work with, I own and it does everything

kikicoco1334

Thank you so much Lex, I will try swap out relays next, thanks for explaining what electronic means, I am pretty new in cars and fixing things.

No i do not have an icarsoft mbII I do have this generic OBC reader that connects to my phone and didn't give any error/codes. When I tried to pull log it just says "no codes are stored in ECU" if that's not the samething I'll pick one up.

mrobinso

I wouldn't be surprised if this is actually caused by your multi-function switch (i.e., your turn signal/wiper stalk arm) going bad/faulty.

I don't have this problem, but on my 2005 C240 my wiper will run non-stop when set to position 0 (i.e., off). If I set it to the 'Auto' setting it functions normally (as it should on the auto setting). I have been meaning to replace my multi-function switch but haven't gotten around to it. You need to remove the steering wheel to do it (not super difficult if you are handy - I've already done it once to replace my steering wheel).

Unfortunately there is no good way to test for a faulty multi-function switch, but your symptoms lead to me to further believe the circuitry in these switches can go bad causing strange symptoms. Good luck!

kikicoco1334

Thank you mrobinso, if swapping relay doesn't help I'll give multi function switch a try.

drho2004

Hello, did you ever get this resolved? this just happened to my 2005 w203 this morning. i was reading it could be the front SAM? Please advise, thanks!

bob ssdr

Same exact issue happened to me as well. Front turn signal stays on all the time; even when the ignition key not in place.

slammer111

I believe those are front SAM issues unfortunately. Was the battery disconnected recently?

The turn signal (multifunction) stalk assembly only sends a signal like an on/off switch. There is no logic so to speak. Something that won't turn off is a SAM problem, not a stalk problem.

KevinH2000

You may find this thread helpful.