Vlad-II

I think I have some terrible electrical fault going on with the car I'm not sure what it would be but I'll describe it. This issue happened before, I brought it to the dealer, they cleared the code and the problem went away but now it got much worse. Here's the story:

Once again while I was driving to school the car basically went crazy. The instrument cluster display was completely out of whack. The temperature was reading 185° F, Wipers Went On and Off, SRS blinking on and off, radio turned off, radio controls were lost, all of the errors that happened a month ago reoccured again. And now my CD changer no longer works. My steering wheel radio controls no longer work niether. So I pull over to the shoulder and shut the car off and turn it on, the errors go away and now the SRS issue returns along with a intermittent loss of controls for the steering wheel audio functionality.


Intermittent because the sometimes it works sometimes it doesn't. Something triggers the problem to occur. When the steering wheel controls do not work, It appears as AUDIO with dashes. TEL also appears with dashes meaning that the cluster simply doesn't detect the car radio and audio system. So I call the dealer and I told them that I will bring it to them tomorrow to see what is going on.

Now on my way back from school, the problem gets dramatically worse. So many errors suddenly pop up. The instrument cluster display is showing the following errors:

Display Malfunction Visit Workshop, Tele-Aid Visit Workshop, SRS Restraint System Drive To Workshop, Brake Fluid. The instrument cluster also no longer illuminates, I've lost turn signal functionality, the radio is completely dead, it turns on briefly and then shuts off. All interior buttons in the central console do not work and they do not illuminate, they flash on and off. Its as if the car is having an electrical siezure, lol. My windows no longer go up and down, and my sunroof doesn't work. So something went wrong. I can no longer lock the car because there is no central locking anymore and that died.

My central locking system is dead, I have to lock the car manually, there is no security in the car right now, despite the car being shutoff the instrument cluster display is still showing the errors. This time restarting the car does not work either so I'm really worried. I don't want to go long distances with the car anymore because I don't know what could go wrong.


There is something that is seriously wrong with the car and I don't know what it could be. I've been exploring various posts on Benzworld and on this site, I'm coming to the conclusion that it might be the Rear SAM Module, Fuse, or even the Battery and Alternator. The Battery and Alternator warning light did not come on though so I doubt it is the alternator or the battery that is causing the issue. Then again it could be something as simple as a fuse, but I doubt a fuse could cause this problem to occur intermittently.

I took it to AutoZone they told me to go to the dealer, they wouldn't even bother checking the voltages.


I read somewhere that I could check the voltages of the car by pressing a series of buttons on the instrument cluster display anyone know the tecnique of doing that, but if the instrument cluster is malfunctioning that is no longer an option anymore. Anyway does anyone know what it could be? Also is it a simple DIY fix? Thanks.

I will be posting pictures of the issue shortly.

Outkasted24

I was two Hours from Home one night heading back at 2am and My Car did something like this on the Interstate.

Pulled off to the side and looked under the hood.
After much frustration and pushing or tugging on pretty much everything electrical under the hood, The Problem went away and I made it Home.
Next Morning It happened again in the Garage.

Turns Out, The Battery Cables were full of Corrosion and so were some cables near the Transmission.
I Used the toothbrush, Baking Powder and Water mixture on just about every connection I could find, Then Carefully took a Pressure washer and Engine degreaser to the Motor bay.
6 Months Later I'm happy to report, No Issues at all and all terminals are Corrosion free.

Hope that's the problem and easy solution on your C240.

Vlad-II

I'm seriously hoping thats the problem too, its dark now so I can't look at anything but I will definitely post updates tomorrow morning in the daylight. I hope its not the Rear SAM though because that part and labor could easilly be a $1,000 fix, money I do not want to spend right now...

Glyn M Ruck

Something is causing corruption of the CANBUS. Power considerations should be your first check.

Vlad-II

Unfortunately the problem hasn't been solved. I brought the car to the dealer on Friday and they could not reproduce or resurface the problem. Its a transient issue. Something that happens when triggered. Its probably some type of lose electrical component that is causing the issue. Because if it were both SAMs the problem wouldn't be transient or intermittent, it would occur continously. They cleared the SRS issue that was caused by the problem.

I believe its a voltage issue. I do have Aftermarket HIDS installed in the car but I doubt those are the source of the problem solely because they've been on for over a year now. Any thoughts as to what this could be because I'm totally lost..

Glyn, you mentioned power considerations and CANBUS, how would I go about checking that component?

Silver C

Check your battery voltages if they're okay. Usually it's something to do with power failure.. hence your eletrical components are not getting the enough supply of electricity and hence "dying" alternately..

Go back and think about it, do you heat your car everyday and let the battery charge? Does it happen when you car is off for a few days?

Vlad-II

It happens intermittently. The problem started with a loss of Radio and Phone controls. Audio and Phone would have blank dashes instead of displaying the right information. Then from there it got worse..

Glyn M Ruck

Check battery condition by having a proper load test done. Check alternator charging & regulator performance. Check all main power connections and earth straps including the power distribution block on the firewall. Check all appropriate fuses for corrosion.

Intermittent problems are awful to diagnose.

Silver C

If you can't test your battery then I suggest you take it to someone who can. I'd check that first and foremost.

Vlad-II

So the service advisor called me yesterday and told me to bring him a different smart key, (my spare). Apparently the problem hasn't resurfaced after using my secondary key. He drove the car around with the secondary smart key and there were no issues and the cluster of errors did not occur. He advised me to utilize the secondary key for now to see if the problem could resurface again, if not then the key is the culprit. The service advisor also told me that he did a "Water test" which supposedly tests all of these electrical components for corrosion and they could not find anything.

Though I could be overthinking this, I think the radio is the source of the problem because before all of this has occured I would intermittently lose functionality in the steering controls for the radio and telephone. The car has no phone hooked up but it would appear as TEL along with "--------" underneath. Same for Audio it would appear like: "AUDIO" followed by "-------" as if the instrument cluster isn't recieving the right signal for it. It would go and come back untill it finally stays with the dashes. That was the first thing. Then the CD changer isn't detected niether. I put the CDs into the changer but the changer doesn't load the discs and the car says "No CD Changer". So those were the initial problems I've had and then they escalated to what I described above.

This is totally baffling to me though because how could a key cause all of these issues? I mean the key is an old key and has had its share of problems, sometimes it would not unlock and lock the door so I figured the key battery was weak. The range was also pretty low for the smart key as well. Anyway i'm gonna pick up the car from them this afternoon and drive it around to see if the problem resurfaces again.

I'll post updates, I have pictures and video of the errors that occured last week, I'll also post them here. I highly doubt the smart key could cause these major voltage issues though so I know it will still be a problem, but then again I'm not a mechanic nor an electrician so who knows, lol.

When I get the car, I am gonna bring the car to the indy to see if he can check the voltages. Since AutoZone wasn't willing to do so...

Do you guys think that a fault in the the smart key in the ignition could cause these errors to occur?

Glyn M Ruck

There is a limited chance that your other key is achieving something in the EIS that makes the CANBUS more stable. The EIS is the top of the control pyramid.

Everything you are talking about is part of the d2B ring in the car (MOST ring in newer models) which is very voltage dependent for stable operation.

You have not been twisting or bending any of the fibre optic interconnects have you?

Vlad-II

Definitely not. I wouldn't even know where those are. The only alteration that the car has are the aftermarket HID headlights. But I had them on for over a year, any chance that the HIDs are the culprit?

samaritrey

where is the driver side ballast mounted?

mleskovar

Many moons ago I read a post from someone who had their problem traced to the smart key losing connection while driving and giving intermittent failures. In that case the poster had too many keys on their chain and when bumps/holes were hit the weight caused the disconnect problem.

Vlad-II

http://www.youtube.com/watch?v=6tlR87N5WXY

Above is a link to the video that shows the errors that pop up.

The Foreman, Service Advisor, Service Manager including I are all mystified. They suggested removing the HID Lights that were installed to see if thats the case, but they've been on for well over a year now. In fact when the problems arise, the lights are not even on. The problem usually occurs in broad daylight.

The car's HID lights are no where near any electrical components, the ballasts are properly grounded. In fact the HID lights are not even on when the problems occur.

The dealer is clueless, I'm clueless and I would drive the car, but it can be a potential safety hazard if I have no turn signals or brake lights when the issue does arise randomly again. I wish the problem could occur while i'm at the dealer so that they can see it right away, but of course as stated in Murphy's Law, the problem won't happen at your convenience (when i'm at the dealer). SDS will not be able to diagnose the problem until it is a problem. (When it sees all of these errors happening in the car).

The Service Advisor also drove the vehicle and he noticed the problems as well, but of course, he turned the car off and the next morning it did not occur. So I don't know what to do. Here is a detailed list of what occured in the video, that was probably the most severe case it has happened upon recieving the car today, but it wasn't as bad as what you saw in the video where there was a total power outage:

- All Lights Interior Do Not Work
- No Sunroof (Sunroof has to be reprogrammed)
- No Power Functionality
- No Radio Functionality
- All Center Console Buttons Do Not Work
- They No Longer Illuminate At Night
- No Climate Control (No Heat or A/C)
- The Brake Lights Come On (Brake Assist, Parking Brake, Etc..)
- No Turn Signals, No Brake Lights (Fellow Drivers Do Not Know When I'm Changing Lanes, Nor Do They Know When I'm Braking)
- Fuel Guage Is Gone (I Don't Know How Much Fuel I Have In The Car)
-Cars Can't Lock With The Remote Key, Must Lock It Manually

Here Is a Picture of the Audio and Tel with the "Dashes"

Audio With "Dashes" Problem (Precursor To the Above Issues)

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This above problem always happens, PRIOR to the total power functionality of the car.

Here is how it looks under Normal Functionality:


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Once again, let me know what you guys think! I still haven't done the voltage test yet. I might take it to Autozone later to get that done free of charge I hope... Considering I've already lost well over $400.00 at the dealer for an unfixed problem..

samaritrey

I would guess it is something expensive or so simple. I do know that the rear sam controls the fuel gauge and assume the front sam does the turn signals so they could both be bad or damaged or not talking or something wish i could help strange issue.

Silver C

Double.

Silver C

Found out what's the culprit yet?

Vlad-II

Yes, I think I may have some more clues. Though I don't think its related to the Audio Control and Telephone Control Steering Wheel Functionality...

Ok so here's today's story. On the way back from school, it started to rain and the windows inside became fogged. So I turn on the A/C in effort to make it cool inside to match the outside air temp and low and behold the problem occured immediately. All of the issues I mentioned above came back, it starts out mild and then it gets progressively worse.

A/C & CLIMATE CONTROL COULD BE THE POSSIBLE TRIGGERING MECHANISM
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So when I got home I played around with it again, the temp display read 185°F and the beam light indicator came on, horn was blown even though I didn't press the horn. Turn signals went array, pretty much everything I described (plethora of errors and warning lights) above occured all over again with increasing intensity.


PROBLEMS ARE WORSE WHEN CAR IS IDLED AND A/C IS ON
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And then, while idle and fiddling around, something quite suprising came up, Battery and Alternator with a RED screen. That BRIEFLY showed on the display and then immediately went away. It was on for a good 5 - 10 seconds and then it dissappeared. So then I shut off the car and turn it back on errors resumed. But the Battery and Alternator DOES NOT return. It also seems like a likely suspect, but again the car says otherwise.. It seems like the more I start and shutoff the car, the errors come on with greater intensity, (obviously it takes more power to start the car than anything else) but the "triggering" mechanism seems to be the climate control system, particularly the Air Conditioning. However the A/C doesn't trigger the problem directly. The prerequisite, is the Audio and Telephone with the Dashes that I shown in the above picture. That has to occur FIRST, before turning on the A/C to trigger the errors.

So I think we're getting somewhere, but still not close. When putting the car on Dyno Mode (Pressing Trip Reset 3X while Key is in Position 1), the Voltage Reads somewhere 14.4 - 14.7 volts during idle, while the problem occurs. I don't remember the exact number. That is what is coming out of the battery.

I'm gonna definitely bring it to AutoZone or Pep Boys tomorrow to get it checked out and then ultimately I'll bring it again to the dealer, with the problem at hand. But I want to nail this down before I do so.

I have no idea how in the world the Climate Control System could interfere with the Electronics, Canbus and EIS and the Voltage of the Car but it somehow does.

I'M RULING OUT THE HIDS..
---------------------------
I'm now officially ruling out the HIDs because the lights are not even on when this occurs. I don't know what kind of role they play in terms of how frequently the error occurs while they are on, but they don't seem to be related. The Service Advisor and the dealer was quick to blame the HIDs. The Ballasts are also no where near any components (or the ESP for that matter). They are mounted on the lamp housing itself and are both properly grounded.

I'm thinking something in the wiring or in the A/C or Climate Control or something in the center console in general is not being regulated properly and is screwing around with the car's computer. But I can't figure out what it is, because I have no idea. It could be something as simple as bad wiring, to something as complex as the SAM. But then again its expected, Mercedes Benzs are great cars, but they're electronical systems are crap. (Same story for a lot of German Cars).

So for the experienced members, Any thoughts anyone?

Vlad-II

I guess I'll also be a bit more detailed, with what is going on in the Instrument Cluster.

When the problem arises the Instrument Cluster goes out of whack. The lights come on and off, blinks on and off, etc.. The SRS and TELE AID errors now come on. In fact sometimes an "emergency call" will attempt to be made without me even initiating it, lol. The car simply does it on its on of course the call will fail because I'm not suscribed to TELE-AID and MBRACE.

Next the Brake Light and High Beam Indicator flashes on and off repeatedly. Then the Turn Signals will not work during the "seizure". The reason I mention seizure is because the cluster's lights are blinking profusely on and off along with the center console lights.

What is weird is that the blinking and errors will somewhat stop (Blinkers return to normal and temperature no longer reads 185° F) and when this occurs, the problem goes away temporarilly only to re-initiate itself. To re-initiate the Climate Control has to be turned on and off.

mleskovar

Have you tested the battery yet? The running voltage shows the alternator working but I don't see where you've tested the battery.....unless the dealer did.

Vlad-II

That's because I haven't tested the voltages yet. What are ideal voltages to look for when testing?

mleskovar

12.68 = 100%, 12.24 = 50%, 12.06 = 25% Also, you should have it load tested, especialy considering your symptoms.

Vlad-II

Ok I'm gonna test it tomorrow. I also noticed that the Battery/Alternator Light Stays On Longer. This time the A/C wasn't the culprit. I have a strong feeling that it is the Voltage Regulator on the Alternator that is going bad and that is causing the symptoms. Whenever some component in the car demands more power the symptoms occur. Ill post the results of the voltage test tomorrow. Thanks mleskovar for those numbers.

Vlad

Vlad-II

A couple of members on BW (Benz World), stated that the Voltage Regulator is the likely suspect, rather than the alternator itself. Hence why the sensor read "Battery/Alternator" Visit Workshop.