A Bizzare ELECTRICAL Problem - 02' W203 C240
#26
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Audi A4 Quattro 2013
This probably doesnt help but I'll post in case the off chance.
I did hear from a friend who had an pre-facelift (like yours) and the dealer had to replace the radio. I read later that the radio can cause problems. Sorry if it seams silly to post this as you may already have ruled it out, but I thought whatever info cant hurt; worst case its not relevant.
I did hear from a friend who had an pre-facelift (like yours) and the dealer had to replace the radio. I read later that the radio can cause problems. Sorry if it seams silly to post this as you may already have ruled it out, but I thought whatever info cant hurt; worst case its not relevant.
#27
Member
Thread Starter
This probably doesnt help but I'll post in case the off chance.
I did hear from a friend who had an pre-facelift (like yours) and the dealer had to replace the radio. I read later that the radio can cause problems. Sorry if it seams silly to post this as you may already have ruled it out, but I thought whatever info cant hurt; worst case its not relevant.
I did hear from a friend who had an pre-facelift (like yours) and the dealer had to replace the radio. I read later that the radio can cause problems. Sorry if it seams silly to post this as you may already have ruled it out, but I thought whatever info cant hurt; worst case its not relevant.
#28
MBWorld Fanatic!
Sounds as if it is a intermittent bad connection to earth.I would spend a little time finding earthing points , remove ,& clean them.
#29
Member
Thread Starter
So the voltage test was done yesterday, turns out there is nothing wrong with the battery. And if the battery is functioning well, that means the alternator is functioning well. It could be that the alternator is "beginning" to go bad hence why the problems are occuring intermittently. I've also noticed that when the car is started cold, there is some weird grinding like sound that comes from it.
Last edited by Vlad-II; 05-20-2011 at 08:06 PM.
#31
Member
Thread Starter
Ok, so two days and still no problem. Everything appears normal. After I did the voltage test everything seems normal now its so weird lol. The car has been behaving normally..
#32
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2002 CL600, VW W8, Dodge 2500 Cummins
Voltage Related for Sure
Could be bad ground. That would explain the intermittent aspects. Low voltage would cause the weird behaviors also. Low voltage or low amperage. If the regulator, battery, or alternator cannot supply enough current either because they are defective or because of a poor ground or other connector, then voltage could be OK but the current deficient, like a faucet that has plenty of pressure, but is partiality closed. Same effect as using wire that is too small. Turning on the AC ups the current draw considerably as does the radio amp. If they are trying to draw amps and cannot get them, then voltage will drop across the system and all the problems will appear.
![drive](https://mbworld.org/forums/images/smilies/driving.gif)
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MercBzC240 (10-30-2022)
#33
Member
Thread Starter
Yeah, this is probably the most frustrating problem I've ever had with the car. And I could check all of the earthing points and ground connectors but I simply wouldn't know how and I don't have the money to shell out anymore and give to the dealer. (I already lost $400.00 dollars for nothing).
Anyway these are the two likely suspects:
1. Voltage Regulator - 60% Liklihood
2. Alternator - 20% Liklihood
3. Radio - 20% Liklihood
Now the reason why I mention the Radio as a suspect is because this occurs:
![](http://img860.imageshack.us/img860/7061/imag0129o.jpg)
The image above is the PREREQUISITE to the Array of errors that will soon follow. Sometimes nothing happens and it stays like this, but more and more often the errors suddenly pop up more often now after the Audio appears with the Dashes. On Friday the Battery and Alternator light came on once again. So the Alternator and Voltage Regulator still to me is the very likely suspect in the problem.
Then the array of errors and the instrument cluster goes crazy along with the entire car. Merzman and Annoymousmouse I truly support your notion and it could very well be the Radio as Annoymousmouse pointed out or it could be the Alternator or even some lose wiring or even a bad ground. The one thing that I have to say though when the problem happens is that the Radio is ALWAYS on. The tends to trigger the problem. The problem happened again two days ago (Friday and Saturday) today it gave me a break. But when the problem happened on Friday, it was persistent this time. And it lasted a whole day so I figured it would last until Tuesday so that I could bring it to the dealer again, and low and behold the problem is gone again. If it could remain permanent that would be awesome because the SDS will be able to determine where the fault is, however if its intermittant there is nothing that the dealer, nor SDS can do to figure it out.
Here is another thing that I noticed which makes the Alternator's Voltage Regulator a Likely Suspect:
So the problem happened on Friday and I figured I'd try to trigger it again and I did. When the car is on idle and the problem occurs, I shut it off and turn it back on, and the Audio with bars shows up on the screen like what you see above, I rev the car a bit to about 2,000 RPMs and then the cluster of problems then occurs. So it seems as if the voltages aren't being regulated, because when you rev the engine the belts spin faster thus the alternator spins faster and it its the Voltage Regulator's job to keep the voltages stable when revving, so if it is not doing that then it could be malfunctioning.
I've mentioned before that the Climate Control mechanism was the trigger in the previous post but on Friday nothing specifically triggered the problem, it occured on its own, the radio was on though, so maybe the radio triggered it this time. What would be the most cost effective solution to this problem? Could it be the Voltage Regulator?
Anyway these are the two likely suspects:
1. Voltage Regulator - 60% Liklihood
2. Alternator - 20% Liklihood
3. Radio - 20% Liklihood
Now the reason why I mention the Radio as a suspect is because this occurs:
![](http://img860.imageshack.us/img860/7061/imag0129o.jpg)
The image above is the PREREQUISITE to the Array of errors that will soon follow. Sometimes nothing happens and it stays like this, but more and more often the errors suddenly pop up more often now after the Audio appears with the Dashes. On Friday the Battery and Alternator light came on once again. So the Alternator and Voltage Regulator still to me is the very likely suspect in the problem.
Then the array of errors and the instrument cluster goes crazy along with the entire car. Merzman and Annoymousmouse I truly support your notion and it could very well be the Radio as Annoymousmouse pointed out or it could be the Alternator or even some lose wiring or even a bad ground. The one thing that I have to say though when the problem happens is that the Radio is ALWAYS on. The tends to trigger the problem. The problem happened again two days ago (Friday and Saturday) today it gave me a break. But when the problem happened on Friday, it was persistent this time. And it lasted a whole day so I figured it would last until Tuesday so that I could bring it to the dealer again, and low and behold the problem is gone again. If it could remain permanent that would be awesome because the SDS will be able to determine where the fault is, however if its intermittant there is nothing that the dealer, nor SDS can do to figure it out.
Here is another thing that I noticed which makes the Alternator's Voltage Regulator a Likely Suspect:
So the problem happened on Friday and I figured I'd try to trigger it again and I did. When the car is on idle and the problem occurs, I shut it off and turn it back on, and the Audio with bars shows up on the screen like what you see above, I rev the car a bit to about 2,000 RPMs and then the cluster of problems then occurs. So it seems as if the voltages aren't being regulated, because when you rev the engine the belts spin faster thus the alternator spins faster and it its the Voltage Regulator's job to keep the voltages stable when revving, so if it is not doing that then it could be malfunctioning.
I've mentioned before that the Climate Control mechanism was the trigger in the previous post but on Friday nothing specifically triggered the problem, it occured on its own, the radio was on though, so maybe the radio triggered it this time. What would be the most cost effective solution to this problem? Could it be the Voltage Regulator?
Last edited by Vlad-II; 05-30-2011 at 12:27 AM.
#34
MBWorld Fanatic!
I would suggest buying a cheap multi meter & check your voltage at the battery at idle speed & at 1500 - 2000 rpm when the fault occurs.
Find the fuse to your radio & be ready to pull it when the fault occurs & see whether the electrical system reverts to normal.
Find the fuse to your radio & be ready to pull it when the fault occurs & see whether the electrical system reverts to normal.
#37
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2002 CL600, VW W8, Dodge 2500 Cummins
Autozone?
You can get a free electrical, battery, voltage regulator, and code check at Autozone and such. They will print out the codes for you and are about as accurate as most mechanics. For starters, if you have not done this, disconnect battery, neg first, and clean terminals on battery and cables with a battery tool. If battery is not a jell, check water level and replenish with distilled water. Reconnect snugly. Negative last. Then, get some long leads and a multimeter. Attach the leads to the battery and then drive and fiddle with components. Watch for voltage changes across battery. If you do not have enough voltage, your car will display erratic systems behavior and these may not be predictable- just depends on which component is in line and calling for power first.
You should also try charging the battery with a charger overnight. Often, short runs with high loads will drain the battery and it will not be at optimum charge. This is a good way to see if the issue is lack of voltage.
You should also try charging the battery with a charger overnight. Often, short runs with high loads will drain the battery and it will not be at optimum charge. This is a good way to see if the issue is lack of voltage.
#38
Member
Thread Starter
The problem occured again tonight! I'm really getting desperate now! I must solve this damn problem! And I WILL.![action](https://mbworld.org/forums/images/smilies/action1.gif)
Here is what Scorchie had to say about another owner who owned a 2003 C240 in 2004:
The above was taken directly from a post from 2004. Turns out this user was having the EXACT same problem. Here is a link to the full thread, I didn't want to revive such an old thread from nearly 8 years ago so here is it is:
https://mbworld.org/forums/mercedes-...t-problem.html
Turns out this user's solution was replacing the sunroof switch. Apparently the sunroof was sending "funky" data to the canbus and EIS which resulted in the errors. They initially replaced the ignition switch in his car and that was not the solution and then they eventually traced the problem to the overhead console and sunroof.
So the above procedure that Scorchie mentioned had to do with checking various wires and finding the short which a few of you had mentioned. Now my question is where is all of this stuff located at and how would I go about checking these things. I still have to do the voltage test tomorrow as well I'm hoping the problem will occur again so that I can check it.
I think I may have the same problem as him because he mentioned all of the symptoms that I have, the only thing he did NOT mention was the loss of the radio controls on the steering wheel, in my case that occurs FIRST prior to the remaining problem.
So now I'm starting to think that it may have to do with something in the center console because I noticed that when the car is OFF the problem goes away it only occurs when the car is turned on and idling, and when I turn the radio ON. The radio immediately shuts off followed by everything else and as soon as I turn the radio back on it turns off again. Turning the Radio ON and OFF interacts with the problem. And what was interesting a two weeks back, turning the AC ON and OFF interacted with the problem. The other user from 2004 did NOT mention that it was his radio that was the source of the problem. And his Battery / Alternator warning light DID NOT come on.
Here is a few more things that I want to mention this was the service report from Rallye Motors, a flagship MB, dealer in Long Island, NY.
(Roughly $400.00 Spent Thus Far, and They Couldn't even determine the problem...)
A. C/S SRS DISPLAYS AND DISPLAY MALFUNCTION ON INSTRUMENT CLUSTER
910000 CHECK TIME NTDB
77939 PERFORM SHORT TEST (HAS FAULT IN SRS UNIT-B1075 CAN COMMUNICATION FAULT). HAS ALSO A LOT OF CAN PROBLEM CODES.
CHECK ACTUAL COMPLAINT. R_R BOTH CAN DISTRIBUTER BLOCKS(X30/7 AND X30/4(. INSPECT THEM FOR WATER DAMAGE AND CORRECT POSITION-OK. NO COROSION ON CANBUS CONNECTOR. AT THIS TIME ALL SYSTEM ON CANBUS WORKING CORRECTLY. SUGGEST TO REPLACE FRONT SAM. BASED ON CANBUS FAULT AND CUSTOMER COMPLAINTS, VERY POSSIBLE FRONT SAM MAY CAUSE THAT PROBLEM. (CAN'T PROOVE THAT 100% BECAUSE IT IS WORKING CORRECTLY NOW).
And they couldn't prove it 100% because the problem is an intermittent problem. If it was a permanent issue obviously we would've known long ago the cause..
I've checked all "earthing" points that some of you guys mentioned, they seem to be OK no corrosion or rust. The HIDs are the only earthing points that have some rust in them but it doesn't seem to be that bad. I highly doubt the HIDs are the source of the problem though because as i've mentioned this occurs during the day as well when the lights are not even on.
![action](https://mbworld.org/forums/images/smilies/action1.gif)
Here is what Scorchie had to say about another owner who owned a 2003 C240 in 2004:
Originally Posted by scorchie
It's obvious there is a CAN communications problem... what is causing it may be difficult to track down. If the EIS has been replaced, then let's assume that one is good. There may be a short in the wiring from the EIS to the CAN termination block. There could be a short in ANY of those wires. I believe there is a procedure in WIS for tracking down those errors, but if there isn't, I would go about troubleshooting this by removing each device from CAN until the error disappears. Unfortunately, disconnecting some items may cause problems, so it has to be done with some knowledge.
-s-
-s-
https://mbworld.org/forums/mercedes-...t-problem.html
Turns out this user's solution was replacing the sunroof switch. Apparently the sunroof was sending "funky" data to the canbus and EIS which resulted in the errors. They initially replaced the ignition switch in his car and that was not the solution and then they eventually traced the problem to the overhead console and sunroof.
So the above procedure that Scorchie mentioned had to do with checking various wires and finding the short which a few of you had mentioned. Now my question is where is all of this stuff located at and how would I go about checking these things. I still have to do the voltage test tomorrow as well I'm hoping the problem will occur again so that I can check it.
I think I may have the same problem as him because he mentioned all of the symptoms that I have, the only thing he did NOT mention was the loss of the radio controls on the steering wheel, in my case that occurs FIRST prior to the remaining problem.
So now I'm starting to think that it may have to do with something in the center console because I noticed that when the car is OFF the problem goes away it only occurs when the car is turned on and idling, and when I turn the radio ON. The radio immediately shuts off followed by everything else and as soon as I turn the radio back on it turns off again. Turning the Radio ON and OFF interacts with the problem. And what was interesting a two weeks back, turning the AC ON and OFF interacted with the problem. The other user from 2004 did NOT mention that it was his radio that was the source of the problem. And his Battery / Alternator warning light DID NOT come on.
Here is a few more things that I want to mention this was the service report from Rallye Motors, a flagship MB, dealer in Long Island, NY.
(Roughly $400.00 Spent Thus Far, and They Couldn't even determine the problem...)
A. C/S SRS DISPLAYS AND DISPLAY MALFUNCTION ON INSTRUMENT CLUSTER
910000 CHECK TIME NTDB
77939 PERFORM SHORT TEST (HAS FAULT IN SRS UNIT-B1075 CAN COMMUNICATION FAULT). HAS ALSO A LOT OF CAN PROBLEM CODES.
CHECK ACTUAL COMPLAINT. R_R BOTH CAN DISTRIBUTER BLOCKS(X30/7 AND X30/4(. INSPECT THEM FOR WATER DAMAGE AND CORRECT POSITION-OK. NO COROSION ON CANBUS CONNECTOR. AT THIS TIME ALL SYSTEM ON CANBUS WORKING CORRECTLY. SUGGEST TO REPLACE FRONT SAM. BASED ON CANBUS FAULT AND CUSTOMER COMPLAINTS, VERY POSSIBLE FRONT SAM MAY CAUSE THAT PROBLEM. (CAN'T PROOVE THAT 100% BECAUSE IT IS WORKING CORRECTLY NOW).
And they couldn't prove it 100% because the problem is an intermittent problem. If it was a permanent issue obviously we would've known long ago the cause..
I've checked all "earthing" points that some of you guys mentioned, they seem to be OK no corrosion or rust. The HIDs are the only earthing points that have some rust in them but it doesn't seem to be that bad. I highly doubt the HIDs are the source of the problem though because as i've mentioned this occurs during the day as well when the lights are not even on.
Last edited by Vlad-II; 06-01-2011 at 12:30 AM.
#39
MBWorld Fanatic!
If you have an electrical problem in a system & do not know which circuit is causing it , you can pull the fuse to each relevant circuit in turn & therefore isolate each circuit in turn & see whether the fault is evident.
It helps to narrow down where the fault is.
You can then attack the faulty circuit . eg run new temporary wiring to the appliance or check appliance itself for faults.
This method was used to remove earth faults in DC systems on ships. Same principle here.
Good luck.
It helps to narrow down where the fault is.
You can then attack the faulty circuit . eg run new temporary wiring to the appliance or check appliance itself for faults.
This method was used to remove earth faults in DC systems on ships. Same principle here.
Good luck.
#40
Member
Thread Starter
If you have an electrical problem in a system & do not know which circuit is causing it , you can pull the fuse to each relevant circuit in turn & therefore isolate each circuit in turn & see whether the fault is evident.
It helps to narrow down where the fault is.
You can then attack the faulty circuit . eg run new temporary wiring to the appliance or check appliance itself for faults.
This method was used to remove earth faults in DC systems on ships. Same principle here.
Good luck.
It helps to narrow down where the fault is.
You can then attack the faulty circuit . eg run new temporary wiring to the appliance or check appliance itself for faults.
This method was used to remove earth faults in DC systems on ships. Same principle here.
Good luck.
Thanks Again For The Support Everyone!
![Smilie](https://mbworld.org/forums/images/smilies/smile.gif)
-Vlad
#41
MBWorld Fanatic!
You should have a fuse list booklet in your manual pack which came with the car.
In the w204 it was in my jack kit in the boot.
Someone with a w203 will know.
In the w204 it was in my jack kit in the boot.
Someone with a w203 will know.
#42
MBWorld Fanatic!
It would be helpful for you to obtain a wiring diagram for the car...someome?
#43
-KCMO C320
#44
Member
Thread Starter
Carsy and everyone else let me say that you have all be extremely helpful in this matter and I really gladly appreciate all of your help and support in this matter. Thank You.
Now as for the update, the problem unfortunately hasn't resurfaced since I last mentioned it. I was kind hoping it woukld so I could try to pinpoint the source and use the wonderful references that Carsy provided.
Ill keep you all posted. Kcmoc320 is it similar to the problem that I'm having? With the instrument cluster giving you problems?
Now as for the update, the problem unfortunately hasn't resurfaced since I last mentioned it. I was kind hoping it woukld so I could try to pinpoint the source and use the wonderful references that Carsy provided.
Ill keep you all posted. Kcmoc320 is it similar to the problem that I'm having? With the instrument cluster giving you problems?
#45
Super Moderator
start with checking fuses and if they are fine check the fuse on the radio itself.
#46
Member
Thread Starter
I've checked all fuses, and I cannot seem to determine where the radio fuse is. I don't want to pull out random fuses and mess up anything in the car. I've looked at the diagrams, that some of you guys kindly posted, I found the Front SAM, the Passenger SAM and the REAR Sam, however they all seem to be fine. The fuses that I'm looking for are actually not present. The fuse numbers for the CD Changer and Audio Control simply do not show. And they are mostly empty.
I've come to the realization that when these problems occur, all of these fuse components that are described in the passenger and the rear fuse boxes fail. Its as if all of the fuses fail. Which leads me to believe that something is triggering the problem. Hence the symptoms that i mentioned above.
The radio however seems to be the triggering mechanism. But I can't isolate the problem because I cannot find the radio fuse, or its simply not connected. I've checked voltages, the battery seems fine, not sure about the alternator. My guess is that if the battery is working, then the alternator is working too. The problems arise when the car is ON and running. And the prerequisite to the problem as I've mentioned above is the AUDIO with the bars. Along with the TEL with the bars. Its as if the Instrument Cluster doesn't detect the Radio correctly or it doesn't even see it. So I'm now thinking that it could be the RADIO that is causing the problem. Could it be the RADIO System that is causing the issue?
I've come to the realization that when these problems occur, all of these fuse components that are described in the passenger and the rear fuse boxes fail. Its as if all of the fuses fail. Which leads me to believe that something is triggering the problem. Hence the symptoms that i mentioned above.
The radio however seems to be the triggering mechanism. But I can't isolate the problem because I cannot find the radio fuse, or its simply not connected. I've checked voltages, the battery seems fine, not sure about the alternator. My guess is that if the battery is working, then the alternator is working too. The problems arise when the car is ON and running. And the prerequisite to the problem as I've mentioned above is the AUDIO with the bars. Along with the TEL with the bars. Its as if the Instrument Cluster doesn't detect the Radio correctly or it doesn't even see it. So I'm now thinking that it could be the RADIO that is causing the problem. Could it be the RADIO System that is causing the issue?
#47
MBWorld Fanatic!
I've checked all fuses, and I cannot seem to determine where the radio fuse is. I don't want to pull out random fuses and mess up anything in the car. I've looked at the diagrams, that some of you guys kindly posted, I found the Front SAM, the Passenger SAM and the REAR Sam, however they all seem to be fine. The fuses that I'm looking for are actually not present. The fuse numbers for the CD Changer and Audio Control simply do not show. And they are mostly empty.
I've come to the realization that when these problems occur, all of these fuse components that are described in the passenger and the rear fuse boxes fail. Its as if all of the fuses fail. Which leads me to believe that something is triggering the problem. Hence the symptoms that i mentioned above.
The radio however seems to be the triggering mechanism. But I can't isolate the problem because I cannot find the radio fuse, or its simply not connected. I've checked voltages, the battery seems fine, not sure about the alternator. My guess is that if the battery is working, then the alternator is working too. The problems arise when the car is ON and running. And the prerequisite to the problem as I've mentioned above is the AUDIO with the bars. Along with the TEL with the bars. Its as if the Instrument Cluster doesn't detect the Radio correctly or it doesn't even see it. So I'm now thinking that it could be the RADIO that is causing the problem. Could it be the RADIO System that is causing the issue?
I've come to the realization that when these problems occur, all of these fuse components that are described in the passenger and the rear fuse boxes fail. Its as if all of the fuses fail. Which leads me to believe that something is triggering the problem. Hence the symptoms that i mentioned above.
The radio however seems to be the triggering mechanism. But I can't isolate the problem because I cannot find the radio fuse, or its simply not connected. I've checked voltages, the battery seems fine, not sure about the alternator. My guess is that if the battery is working, then the alternator is working too. The problems arise when the car is ON and running. And the prerequisite to the problem as I've mentioned above is the AUDIO with the bars. Along with the TEL with the bars. Its as if the Instrument Cluster doesn't detect the Radio correctly or it doesn't even see it. So I'm now thinking that it could be the RADIO that is causing the problem. Could it be the RADIO System that is causing the issue?
Looking at the fuse list I sent
F 64 is the Audio Navigation & Cockpit mng system .
F 24 is CD Player.
F 26 is the Audio Amplifier which is a large 25 amp! This one draws a lot .
#48
Super Moderator
![](https://staticssl.ibsrv.net/autocomm/Content/MB/mbwambassador2.gif)
![](https://mbworld.org/forums/attachments/c-class-w203/145266d1228848716-car-lighter-isnt-working-w203fuse1.jpg)
![](https://mbworld.org/forums/attachments/c-class-w203/145267d1228848796-car-lighter-isnt-working-w203fuse2.jpg)
There is a fuse on the back of an Audio 10 as well.
![](https://mbworld.org/forums/attachments/c-class-w203/153227d1238457488-can-anyone-identify-these-connectors-audio10_mf2199_hinten.jpg)
![](https://mbworld.org/forums/attachments/c-class-w203/153228d1238457589-can-anyone-identify-these-connectors-audio10_mf2910_hinten_detail.jpg)
https://mbworld.org/forums/attachmen...o10pinouts.pdf
#50
Member
Thread Starter
Ok, thanks guys for all of the information. Since the radio does turn on, I don't think removing the radio is an option.
What I'm gonna do is i'm gonna remove Fuse 24, 26 from the Driver's Side Fuse Box and 64 from the Front SAM Module to see if the problem and plethora of errors resumes. Obviously power will no longer be supplied to those components since the fuses are gone and removed. Now if the problem persists, then we can rule out the radio and the climate control as the cause, and we now know it definitely is the Alternator / Voltage Regulator that is the culprit.
I'll let you guy know what happens.
What I'm gonna do is i'm gonna remove Fuse 24, 26 from the Driver's Side Fuse Box and 64 from the Front SAM Module to see if the problem and plethora of errors resumes. Obviously power will no longer be supplied to those components since the fuses are gone and removed. Now if the problem persists, then we can rule out the radio and the climate control as the cause, and we now know it definitely is the Alternator / Voltage Regulator that is the culprit.
I'll let you guy know what happens.