crazy4life

Went through a touch less car wash and now the right turn signal is not working. Any ideas on what the problem could be?

Thanks

ThatsMyDawg

Likely there is a small/hairline crack in the lens that has allowed water to short out the light. Higher than normal rain water pressure can do that. Sometimes you will see fog, etc. in that lens as well. Get down and look closely and if not visible with naked eye you sometimes can find the crack by running your fingernail of the lens to find it. Sorta like searching a clear roll of tape for the starting point.

crconsulting

Unfortunately somewhat common,

https://mbworld.org/forums/sl-class-...-15-sl400.html

https://mbworld.org/forums/sl-class-...ght-issue.html

https://mbworld.org/forums/sl-class-...wersupply.html

Good Luck

Montreal300

There are 12 LED's that make up the turn signal. Arranged as groups of 2, 3 and 7 LED's on 3 individual circuit boards. The dumb thing is that if one board shorts out, all three go off line. They are shielded at the top of the headlight but still exposed to any water that gets into the main casing so as TMD says, check for cracks. Just so you know, there are very few people that will attempt to take the casing apart and replace the LED board that went south. Cost is around $1,000 USD.
A new headlight is around $1,800 USD from Autohaus. Be very wary of buying used headlights because you stand a 1 in 3 chance of getting a good one. At $400 to $600 each used, you would be better off with a new one.
The other item to check is the headlight module mounted to the bottom of the headlight casing. It is very poorly designed to keep water out and is known to fail on the R231. Take yours apart and check the terminals for corrosion in the multi pin connection and then check the inside of the module for water and or corrosion.
If the module is the problem, buy a new one if possible because even though you can find them on eBay, they might not be designed for the R231. The same module is used on a lot of MB products. Having said that, if that module fails it usually takes down the whole headlight.
Another thing to note is that up to 2015 you can replace anything in and around the headlight. After 2014, the new headlight has to be programmed.
Good luck!

crazy4life

Thanks for the help everyone. Seems like it is the turn signal and the parking light. Headlight works fine.

crazy4life

Does anyone know if I can take the headlight control module from the left headlight and switch it to the right headlight? Would like to eliminate the control module from the the source of why my right turn signall not working. The single line of lights for the parking light was working and also the side marker light was working and they are both inoperable now,
2013 SL550
Thanks

crconsulting

They are interchangeable….

If you turned the headlights on without both modules hooked up, or one of the modules is defective and hooked it up to the other side, you probably need to clear the errors with XENTRY before the lights will operate properly again.


Good Luck!

crazy4life

Thanks for the response. Removed the tire and the inner fender cover with ease. There are 4 torx 20 screws that hold the module in. The front two are easy to get to. I don’t know what magician can get to the forward two screws. Tried for an hour with various attachments and could not get to them. Gave up and went to bar. Have to try to come up with a 90 degree torx wrench. There is only 1 inch of space to get something in there on the front passenger side screw. Taking the bumper off seems pretty easy maybe i will go that route since i want to swap modules.

crazy4life

UPDATE
Replaced the headlight module and had it programmed by the BenzNinja and all is well. The old module was full of water from the carwash.