Hey Scotty, I have a 2000 Mercedes Benz SLK230 with 166,000 miles. I bought it last year used with 155,000 miles as my first car. It has been my daily driver since. I just have one question about this BAS ASR light that pops up occasionally. Sometimes when I am driving, the light will just randomly pop up. Sometimes it stays on for a few seconds, minutes, or even more than 30 mins. It only happens a few times a month. The light will usually go away when I continue to drive or it will go away after shutting off the car.
I spoke to my mechanic and he owns an older Mercedes CL500, and he says that the light also pops up on his car once in a while too, but it does not really affect anything. He says it is merely a speed sensor on the wheel that is old.
I am wondering is it worth replacing or should I just live with it? Does the wheel speed sensor even do anything important?
I cannot use a normal scan tool on BAS ASR codes, I heard I would have to go to a dealer.
I would replace the wheel speed sensor cause it is security-related. It is not a big deal, really. Just one small sensor, pfff. I wish this was the biggest problem with my Benz.
But before you do, try examining the sensor wires and connectors for visible damage (fixing what can be fixed), connect and disconnect the faulty sensor´s (or all sensors´) connectors, and spray the wires and the connectors off with some contact-improving spray. It could be just some moisture in a connector hampering electric signals transmittal.
Thank you for the tips. This “problem” is really more of an annoyance haha. It’s just something that occurs once in a while. Sometimes I’ll get it several times in a row, sometimes weeks go by and it doesn’t happen.
I’ll definitely try cleaning the sensors. It only happens when driving, not really when I step on the brake and come to a stop, that rules out the brake light switch for the most part. Also my battery is only 8 months old so it shouldn’t be some electrical glitch.
You´re welcome.
The most probable scenario is imo that just one of the sensor wires has gone (is slowly going) bad. Ive read on the Internet that this is pretty common.
I am cheap: I visually found the faulty place on my wire and (in order to avoid wire replacement) fixed the crack with some chinese "liquid electrical insulation" compound.
I was ready to pay for replacement, if this hadn´t worked, but this happened like 5 years ago, and I have not seen this light again ever after.
Also bear in mind that this is a safety issue, not just an annoyance: when this light is on, you not only lose acceleration slip control, but you also suffer a decrease in braking time and distance: without BAS, braking takes longer.