burgerbreakfast

Hello

My 2001 C180 Sportcoupe has a problem. After a powerwash my speedometer stopped working along with the abs, esp, bas systems. I have no idea if it's actually water damage as no fuses are blown and I don't know where else to check.
After many hours of googling I found that people have replaced rear wheel speed sensors or the brake light switch and got it fixed. The obd scanner showed faults with CAN communication with control unit N47-5(ESP, SPS and BAS control module P0600) and also wheel speed sensor(P0500). So from that, could it also be the yaw rate sensor or esp module?

Any help would be appreciated.

slammer111

Water obviously got in somewhere.

Are there any other systems that stopped working? Be as specific as you can. Do all the lights (turn signals, sidemarkers etc.) work?

Did you power wash the engine bay?

burgerbreakfast

No, I didn't wash the engine bay. Only outside and wheel wells.
After the wash when I started the car, it beeped and warned me of only the ABS, ESP, BAS systems not working and the speedometer. From then abs light stays on.
I don't know if its relevant, but "brake lining wear" has been on the dash since I got the car.

112233

If the coal water drains are clogged (and they will) water can flood the front SAM. I would open the engine bay fuse box (front SAM is there too) and look for water.

C230 Sport Coup

Definately water instrusion. I've had this several times after a bad rain.
Headlights on constant as well.
Check the SAM and other wise let it dry out, or maybe try a leaf blower?
Never tried that myself but seems like it might help.
If it worked before you washed it, and it suddenly stopped working after washing...
welll...it's always the last thing you did to the car.

KevinH2000

This is a bit of a stretch, but I am wondering whether your pressure washer dislodged or damaged the connector or wiring harness that brings the signal from the sensor ring in the wheel hub to the SAM. Wheel sensor connector. This link may help.

I agree with the other posters who suggested that water intrusion into the front SAM is another possibility.

Good luck.

C230 Sport Coup

Yeah, I had a wheel sensor fail during a torrential rain. It's interesting driving with bad wheel sensor,
you can do it if you go easy on the throttle but dash lights up like a Christmas tree with errors. The next morning
the car also was quasi dead, no dash panel, lights on constant but started and ran.
Car went to the shop, they couldn't read the codes or anything. They parked it inside for a few days,
dried out, came back to life, and were able to see which sensor was bad and replace it.
Maybe the sensor wasn't even bad, and water go in, who knows.
This has happened now about 3 times. Fortunately it's parked inside now.
I've never had another wheel sensor fail in 256K miles and still going (for how long
remains to be seen).

burgerbreakfast

Thank you guys for the input. Currently I am waiting for new wheel speed sensors for the rear wheels.
If it really is the front sam that got damaged then I don't know what to do. It has also been a long time since it happened so everything has most definitely dried out already.
A friend of mine with the same car told me that he had the same problem and it was the esp module in the trunk where the wheel speed sensors hook up to.

burgerbreakfast

Hello again.

I now have checked the front sam unit which doesn't seem to have any water damage related corrosion. Although when unplugging the wires, there was some oil in one of the connectors which isn't quite clear to me, is it there for protection?

I also got to changing the rear wheel speed sensors, but when I wanted to connect them, I realised that the previous owner had perhaps broken the connector and spliced the wire instead so I don't know if i have to do the same or replace the connector block thing.

Imgur link for images