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Was driving highway speed with Distronic engaged and got the triangle and Distronic Inoperative. Also, was getting the other stuff mentioned in the title. Park Assist resets on restart, but goes inoperative at door-lock speed, about 9 MPH. The other stuff is out of commission on restart.
I was thinking wheel sensor because that was the only thing that I could think of that might be tied to all four systems. They're each pretty independent of each other.... And, when I searched the words in title, got one hit:
And, it was the wheel sensor-- twice over the years-- for that thread starter, so guess I was guessing right...
I haven't used my STAR diagnostic yet... bloody hot here... But, was wondering if anyone has any tips on how to find out which sensor it is and how to replace. I.e. what diagnostic should I run? Thought I'd start with the whole car check and see what comes up. Haven't used STAR much as of late-- knock on wood-- but, IIRC, you can check each system separately and there's a memory of when any anomaly occurred.
To follow up: Ran the DAS and under ABR - Adaptive Brake- (something lost in translation, I guess), it showed faults on 3 of the 4 wheel sensors. But one was repeated twice??? DAS suggested replacing all four sensors (guess that's what the dealer would do at part's cost of about $150 per sensor). I cleared the faults and did the recommended reprogramming of the "control module" under the ABR's "Control unit adaptions"; lots clicking and liquid sounds when you do that. Also, ran a few more checks of other systems and got a message or something, "One of speed sensors implausible". Don't recall which system I checked, but to me that confirmed one sensor was completely bad...
Then drove the car. Got to door-lock speed (about 9 MPH) and ABS and ESP Inoperative came back. Ran DAS again and only one fault on ABR came up: L6/4- right rear sensor. That was the one listed twice on the first test. So, I suppose I found the culprit. Ordered two rear sensors on ebay for about $16 (left rear was stored on first test, so thought it good to have a spare on hand if that fault returns). BTW, left and right are interchangeable, but front and rear are different.
So, now all I have to do is wait for the part and see how hard/easy it is to replace.
For anyone similarly situated but not having DAS, one solution might be to order 4 new sensors. 25% chance of fixing it on first try, 33% on the second, etc. What I'm not sure of is whether the system will reset just by replacing the sensors or whether the faults have to be cleared with STAR????
Anyway, thought I'd share since I started the question.
You're welcome slcbbrown and thanks for the link EasyPhil.
The link adds that the rings on the axle that feed the speed sensors get dirty and can trigger ABS and ESP shut down. And, that they're hard to get to, but you can use brake cleaner and spray it in the holes where the sensors fit. I think I'm getting some of that too and that would explain faults on two other sensors that didn't come back after clearing with STAR.
Occasionally, I get an ABS and EPS warning on start up, but it always clears after the car gets rolling. It's not bothersome enough to go through the effort of removing wheels, cleaning and so forth. However, this latest snafu is almost certainly an open circuit on the one sensor. I was driving in a 75 mph speed zone when the distronic shut down, so maybe some road debris damaged the wiring on the sensor. As a fellow enthusiast remarked, "At least it didn't lock the wheels and send you spinning out of control."
You're welcome slcbbrown and thanks for the link EasyPhil.
The link adds that the rings on the axle that feed the speed sensors get dirty and can trigger ABS and ESP shut down. And, that they're hard to get to, but you can use brake cleaner and spray it in the holes where the sensors fit. I think I'm getting some of that too and that would explain faults on two other sensors that didn't come back after clearing with STAR.
Occasionally, I get an ABS and EPS warning on start up, but it always clears after the car gets rolling. It's not bothersome enough to go through the effort of removing wheels, cleaning and so forth. However, this latest snafu is almost certainly an open circuit on the one sensor. I was driving in a 75 mph speed zone when the distronic shut down, so maybe some road debris damaged the wiring on the sensor. As a fellow enthusiast remarked, "At least it didn't lock the wheels and send you spinning out of control."
For now, waiting on parts... Regards to all...
The takeaway from the thread I created is that there may not be a problem with the sensors. The sensors may just need cleaning along with the reductor ring and spraying brake cleaner in the hole that the sensor goes in does a pretty good job of that. If you "reprogram" the control unit you have to follow that up with the test drive sequence. The process is: Clear codes, recalibrate, test drive sequence.
Thanks again EasyPhil. Sorry I didn't notice that the thread was your's.
I'll see what happens when I replace the sensor, but I wasn't getting the N47-5 faults, only speed sensor faults. IIRC, STAR suggested replacing all sensors and reprogramming N47-5. I did calibrate in ABR--Control unit adaptions, drove the car and only fault that came back was L6/4-- RR sensor. ABS and ESP lights didn't come on until door lock speed. There was also something, somewhere else in DAS about "speed sensor implausible", and I'm pretty sure it listed only L6/4. Also, the intial systems cut off at + 75 mph with distronic engaged, as opposed to doing it on start up or at door lock speed. There's also a test you can do in DAS that measures the voltage of the sensors by rotating the wheel (I assume by hand, >1 rpm or was it >1 rps???). I didn't do that but it's good to know it's there.
But, thanks for the tips. I'll spray some cleaner in the hole when I replace the sensor and see what happens and, if necessary, reprogram using your sequence.
Just curious, did you do the rear sensors? Hard? Easy? I haven't taken the wheel off to see what's in there. Star Finder doesn't really show anything other than the rear hub...
To follow up, received the sensors, replaced the offending one and all is good. ABS, ESP, Distronic and Park Assist now working.
This isn’t exactly rocket surgery, but I didn't know that before I started, so took some pics in case someone wants to know what's involved. Sorry, I'm not too familiar with posting pics, so these may be overkill...
Hardest part was removing the 275-20 rear wheel-- used a long piece of schedule 40 PVC as a cheater on a breaker bar to loosen the lug bolts to save my back. They’re torqued at, I think, >100 ft-lb. And, I find using the jack in the truck works as well or better than a floor jack for lifting the car. I'm always weary of what jack point to use—Hint, raise the car with the button on the dash before starting for a little more room.
The sensor is inboard behind the rotor—takes an E10 star socket. Then you have to peel back the inner liner a little to get to the plugs. Removing the 10mm plastic nut and the lowest push-pin fastener is all that needs to come out.
Only thing that may not be obvious is that there’s a metal clip holding the sockets in. The upper plug is for the brake-pad wear sensor. Just pry the bottom end of the clip out a little with a screw driver or take it off altogether (see pic).
The old sensor didn’t show any damage and when I checked its ohm reading with a meter (DMM) set at 2000K ohms, I got about 400 for the old and about 500 for the new. So, I don’t know if that tells you anything. I’ve read you can use the DMM to read the AC voltage output of the sensor by spinning the rotor by hand. IIRC, these sensors work by spinning a series of magnets on the axle and the coil on the sensor generates an AC sine wave voltage that all the computers use to measure wheel speed. STAR/DAS allows you to measure the actual voltage, but there’s no reason you couldn't measure the output manually with a DMM by spinning the rotor by hand. You would have to figure out how to attach the DMM to the pins in the plug and spin the rotor; perhaps with alligator clips...
Bottom line, these sensors are not that expensive online, so if you don’t have STAR/DAS, I’d just get all 4 and start replacing them one at a time. The work involved to test each one hardly justifies the price of each sensor—unless you're paying dealer prices...
In that regard, I guess you get what you pay for. The replacement I bought for $8 works fine, but had two protrusions on the plug verses only one on the original (see last pic). No big deal; just had to grind the protrusions down and the one I replaced fit just fine.
What I don’t know is, if you just replace the sensors, whether the ABS/ESP will just reset without clearing the faults with the STAR diagnostic. EasyPhil’s link gives the STAR procedure if it doesn’t. However-- I'm just guessing here-- I think the ABS/ESP will reset when you reach door-lock speed unless you have the N47-5 codes EasyPhil was getting. I had already cleared my faults and had not driven to door-lock speed prior to replacing the sensor.
I recently had this problem on my 09 S500. The car had been garaged for a few weeks and on driving out of my garage the dashboard lit up. All the consumables were inoperative and the power steering was heavy. Read a lot on the forums and it seemed to pinpoint the brake light switch or the wheel sensors.
I charged the single battery in my model.
On switching off there were no DTC listed and no evidence of there being a problem. The lights came on again shortly after starting and driving off.
I decided to investigate exactly what set the lights coming on. It seemed that the lights simply came on at about 14 mph.
Using my Icarsoft 980 scanner and searching around, with no DTC listed, I looked up the ESP system and there were 4 codes listed. On deleting them the problem disappeared completely.
My rationalisation was that with a low battery condition the code was set and could only be removed by a code reader, but was causing the problem.
Not sure if this is of any help but it gives a low cost check up if the situation occurs.
Two years after the original post, I'm still good with the wheel sensors... Don't recall any ABS, etc. warnings that came back... But, hell, this car gives warnings, e.g. "Park Assist Inoperable", almost on every drive-- every time I pull up behind another car with radar assist... But, I'm pretty sure I haven't cleared any wheel sensor codes in two years...
Barose, for what's it's worth, I think you're on to something. By way of example, IIRC, I've used the MB to jump start another car twice. I have the two battery system, BTW. I think I got an MIL each time. I say "I think", because I jump started a lady at a motel some years ago and vaguely remember, "You shouldn't do that." I jumped my own car last week, not thinking about the last time I did that, and got an MIL and several codes for misfire. I cleared the codes with Xentry and all was good. The car I was jumping wasn't that low. But the misfire, although gone after restart, set the codes and MIL, and needed a reset.
So, I've not heard that the MB is particularly sensitive to voltage fluctuations, but it wouldn't surprise me. Two battery system or not. BTW, I'm wondering how long the big battery in the trunk can last. Mine's been in there forever but I've never had a warning for That. I understand there is a warning for That as well. I've replaced the Starter battery twice in the last five years. I've never even seen the trunk battery....
Anyway, thanks for posting your results... Cool thing about this forum is, you get an email when someone posts to your post... Otherwise, I only check here when I'm stumped or have something to add... And, thanks to all, e.g. BOTUS, who provide much needed info...
Thanks for that reply Mark. My first thought when this happened was my rear battery had failed. A problem I had recently with my 2012 S500. I checked on Wis and the 2009 only had 2 batteries where Eco start/stop is fitted. I took the panel out in the boot and sure enough no battery.
The fact that no DTC was recorded seemed to me to indicate there was no electro/mechanical failure. I also tried to read the DTC's when all the light errors were on the dash (engine running), nothing again. Interestingly it was whilst deleting the set codes the lights went out, seemingly I removed the one code that was hanging up the system.
Thanks again Mark for your response, most encouraging. Brian
the first symptom I had on the ABS sensor failure was the parking brake being odd when I knew I had used it or released it. Happened a few times and no error codes. Then I got the messages in the cluster.
6 guys speratertly all with the same age car in the space of 6 months had the issue (every time was the sensors).... and I see it pop up year after year in batches "designed to fail" two going round on another forum as we speak.
the invisible parking radars on early ones, do pick up lots of issues with other later cars by certain other brands (JLR, Nissan etc.) and are always stored as saved faults. It has no impact on anything else and resets as soon as interference drives away
Two years after the original post, I'm still good with the wheel sensors... Don't recall any ABS, etc. warnings that came back... But, hell, this car gives warnings, e.g. "Park Assist Inoperable", almost on every drive-- every time I pull up behind another car with radar assist... But, I'm pretty sure I haven't cleared any wheel sensor codes in two years..
I've learned to just hit the Park Assist button to turn it off every time I start the car. If I don't, it generally reminds me within a few traffic stops. I was idly looking at the Android screen replacements last night, and noticed that they replace the hard buttons for Park Assist, ESP and chassis up/down... that makes me wonder if one could set it up to turn it off by default. It's just less hassle to turn it on when you want it on, like when you're actually parking.
The Park Assist interference warning doesn't really bother me. I just wish the alarm wasn't... well... so "alarming"....
Back to the thread subject, probably two takeaways here:
1. If you get a perceived wheel sensor warning (ABS, etc), and you have the equipment, try clearing the codes, drive to door-lock speed and see if any codes come back. If, like me, you get one code, you have a good indicator that you have a bad sensor. If like Brian, nothing comes back, it may be just an voltage anomaly that set a hard code. If it comes back intermittently, you probably need new sensors, especially if they're old. Then there's the issue of debris in the magnetic field generator rings, discussed in this thread....
Also, I posited the question on whether just replacing one or all the wheel sensors would clear up the problem without erasing the codes. Based on Brian's experience, apparently not... You need to get into the ABR-- Adaptive Brake-- with some diagnostic source or another... I'm still not sure...
2. Strange voltage fluctuations can trigger hard codes. Mine with jump starting and Brian's ABS with a low battery. In that regard, as has always been my habit, I left the MB running when jumping another car. That's even how the Owner's Manual says to do it. That triggered several hard codes related to misfire in the MB for me. Perhaps, the better practice is to cut off the ignition before attempting to start the other car??? I know, theoretically that could leave you with two cars that won't start... But, if you have a good battery in the donor car and use common sense (don't keep trying if it doesn't start right off), I wouldn't think there should be a problem. Just a thought...
Well put Mark, a consise review of a mysterious problem.
On your jump starting saga, I had a thought that you may have used the battery terminals to connect the jump leads to and it caused a problem. Perhaps if you had connected the jump leads to the post under the plastic cover and the grounding point on the fender it may have prevented a surge. Mercedes provides a system to prevent surges when rapidly charging using the two posts. Hope I am not stating the obvious but it was just a thought.
Best regards Brian (UK)
The Park Assist interference warning doesn't really bother me. I just wish the alarm wasn't... well... so "alarming"....
Back to the thread subject, probably two takeaways here:
1. If you get a perceived wheel sensor warning (ABS, etc), and you have the equipment, try clearing the codes, drive to door-lock speed and see if any codes come back. If, like me, you get one code, you have a good indicator that you have a bad sensor. If like Brian, nothing comes back, it may be just an voltage anomaly that set a hard code. If it comes back intermittently, you probably need new sensors, especially if they're old. Then there's the issue of debris in the magnetic field generator rings, discussed in this thread....
Also, I posited the question on whether just replacing one or all the wheel sensors would clear up the problem without erasing the codes. Based on Brian's experience, apparently not... You need to get into the ABR-- Adaptive Brake-- with some diagnostic source or another... I'm still not sure...
2. Strange voltage fluctuations can trigger hard codes. Mine with jump starting and Brian's ABS with a low battery. In that regard, as has always been my habit, I left the MB running when jumping another car. That's even how the Owner's Manual says to do it. That triggered several hard codes related to misfire in the MB for me. Perhaps, the better practice is to cut off the ignition before attempting to start the other car??? I know, theoretically that could leave you with two cars that won't start... But, if you have a good battery in the donor car and use common sense (don't keep trying if it doesn't start right off), I wouldn't think there should be a problem. Just a thought...
Regards... Mark
I agree voltage issues throw lots of codes... but never seen on safety systems
as I mentioned (if you use the electronic park brake - which is mandatory under law and essential on any kind of slope to save gearbox damage), it uses the ABS sensors for its operation. Mine didn't want to release automatically, although its NOT a feature I use regularly (I was testing during fault finding). But it would also release on its own !!! because of faulty data from deteriorating sensors. This happened numerous times over 6 months just as I was reading lots of owners with the same age car have the same issues. Then I started to get intermiottant messages on the cluster.
As soon as I replaced all 4 sensors everything went to normal and the park brake has never missed a beat in the 3 years since. But on the run up to sensor replacement it was all over the place for 6 months And never seen the ABS message since replacement of the sensors...
Yes, Brian, that's how I did it... On the posts. I can only recall jump starting a car twice in the last 10 years. In earlier days, I would always use a ground other than the battery post... Then my mechanical engineering mind told me not to use an alternate ground because I had noticed that cars of this era usually have small gauge ground wires scattered about the components. My (flawed) thinking was, with all the plastic components, if the ground finds its way through one of those small wires it would fry it like a flashbulb (Flashbulb? "What the hell is a flashbulb?" asks the Millennials...). Typical engineer, overthinking things, especially things electrical. So, I guess the tried and true methods are still best. Thanks for the tip, err... reminder...
Botus, I think we can add a # 3 to my list:
3. Wheel sensors are cheap. If your problem has anything to do with Any system that might even remotely be used to sense wheel speed (I would have never thought of the parking brake-- but, it does disengage automatically if you force movement), go after the wheel sensors. As said, cheap and, relatively easy for the DYI'er to do. (I'm thinking you will most likely will have to erase hard codes to make the warning lights go away. But, probably not, if the warnings just come and go or, are not lit every time on start up.)
Hi guys.
I currently encounter an issue for my s350L.
I had a problem with my normal cruise control. Currently it shows cruise control and speedtronic inoperative. With this error comes out my cruise control unable to use and the night vision also shown inoperative. I uses obd scanner found out the code where no can message was received from control unit n62/1( radar sensors control unit(sgr). Which I assume my car wasn't equipped as I don't have radar in the front centre grill. Moreover I do also found that there is a code saying implausible can message from control module n93(central gateway control unit) parktronic, park pilot. And also s6/2 cockpit switch group: incorrect version - replace component s6/2 (cockpit switch group).
I will attach the picture for the code and my current condition of my car. I had tested the night vision camera and all the parking sensor is working. Now my car only the front parking sensor is not show in the instrument cluster but the rear parking sensor is working normally. Please advice. I had replaced both front wheel speed sensor. All speed sensor is working normally.
It should be pretty safe to wipe all that garbage (especially now you have a record of it) and go for a short drive and see where you are with another check when you get back
often there are year's and year's old messages of garbage stored on the car and you get in a tail spin looking at something that was fixed years back or only popped up during maintenance and some thing was removed to gain access etc.
Don't know enough - try and find out what "s6/2 cockpit switch group" is. It suggests you have the wrong one !! The brake pedal often has two switches, one for the brake lights and another either brake light redundancy or safety cut out for cruise. They used to fail on Merc all day long and are dead cheap. So a quick test there maybe a good idea
It should be pretty safe to wipe all that garbage (especially now you have a record of it) and go for a short drive and see where you are with another check when you get back
often there are year's and year's old messages of garbage stored on the car and you get in a tail spin looking at something that was fixed years back or only popped up during maintenance and some thing was removed to gain access etc.
Don't know enough - try and find out what "s6/2 cockpit switch group" is. It suggests you have the wrong one !! The brake pedal often has two switches, one for the brake lights and another either brake light redundancy or safety cut out for cruise. They used to fail on Merc all day long and are dead cheap. So a quick test there maybe a good idea
Thanks botus for the reply.
May I know how do I do the quick test?
Please advice.
Really appreciate for your help botus.
you should be able to reach the switches... most are simple open circuit, depress the button and it goes closed circuit. An ohm meter should allow that
if you have decent diagnostic, can you see in "live data" the operation
you should be able to reach the switches... most are simple open circuit, depress the button and it goes closed circuit. An ohm meter should allow that
if you have decent diagnostic, can you see in "live data" the operation
you shouldn't just bolt stuff on.... with these exceptions ….. the ABS sensors do just break and the three little level sensors for the suspension. Most other stuff you should diagnose and fix after you know what's' wrong. Mind u at that price and with the build quality these days it isn't going to break the bank is it.
you shouldn't just bolt stuff on.... with these exceptions ….. the ABS sensors do just break and the three little level sensors for the suspension. Most other stuff you should diagnose and fix after you know what's' wrong. Mind u at that price and with the build quality these days it isn't going to break the bank is it.
Understood that. Thanks botus.
I just check out my w221 but it doesn't have a brake switch where is normally on top of the brake pedal. I had remove the lower panel to get access the brake switch but it wasn't there. Please advice.
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