SLcharge

I guess there has been written volumes about water problems of all sorts in the R230, but I will add my 2 cents anyway, in case some have the same problem.

It started with errors like overhead Collum not working, Distronic disengaging during drive, right headlight suddenly turn off, ABC acted strange etc.

I couldn't quite figure out why, until it worsened dramatic, Instrument cluster going cray shutting down, going online again, radio turning off, coming on again, lights not working, etc.

I realized it must have something to do with the Canbus, since all those components could not fail at same time, so I connected Xentry, installed by BenzNinja, and for sure, there was a ****load of Canbus errors.

I started to search for bad connections, first in the drivers side, then rear sam, nothing, but when I lifted the carpet in foot well passenger side, I got the surprise. Water, and a lot of it.

Removed about 1 gallon of water, opened the cable tray, and this is what I found. A totally corroded Canbus C connector.


Now, problem identified, but where did the water come from ???
The carpet was not wet on the upside, so it had to come from somewhere under the dashboard, running down the body shell.
When I opened the bonnet, took away the mesh covering the air intake to the vent system, it was obvious what was wrong. There was about 1½ inch of water down there.
Conclusion : The drain must be blocked, but how to clean it. ???
It turned out to be close to impossible to clean the drain from upside down, so I took out the battery, took out the battery tray, and removed the rubber valve at the outlet of the drain.
And out came the water. Cleaned the inlet, flushed with hot water.

The rubber valve is located at the arrow.


And this is how it looked.



I left it out, did not fit it again, damn thing.

Dried out the underside of the carpet, took about 24 hours with a 9 kW heater.



Replaced the corroded terminals and buzz bar, put everything together again, and all is fine now.
All errors cleared, no issues anymore, like getting a new car.

My advice, remove that rubber valve for good, before it is too late.

A word of advice : Before removing the seat, or disconnecting any other things, disconnect both batteries. After repair errors must be cleared through Xentry. You can do it with your own Xentry or visit a dealer to get all errors cleared.

Tom Manning

Definitely one to add to the maintenance list.

Thanks for taking the time to document and post this.

Paulsl

Thank you so much for your information it's given me some hope I've got a no start after heavy rain had mobile Mercedes mechanic down he told me I need to take passenger chair out can bus problem he also said I shouldn't bother and scrap it which it's not an option must be a way around it fingers crossed 🤞

aegea

U can easily remove the storage compartment forward of a front seat bottom with a few screw removals to access some wiring. Raise seat.

Paulsl

thanks for information I think I will need all the information I can get 👍

MR.AMG.

Hi i have a same issue with can c i my car won't start i have repaired the wiring but it is still doing the same do I have have to clear codes before starting the car?

Paulsl

Hi mate I didn't have to clear any codes are you getting lights on dash? My problem was canbus issue getting in wet with was under passenger seat and carpet seat had to come out then I used electrical spray cleaner and little tooth pick brush good luck if I can help in any way no problem

MR.AMG.

Hi thanks for replying..
Mine got wet too one clip on the green and green/white/earth wire was damaged and the brown/red connector next to it was corroded..
I have rewired new connectors but still have no crank no start issue..
dash lights come on..
terminal 15 has no power i have no idea where that is lol







I will show you the codes on my scanner..