So the pulley is OK? - Yes. The white line I painted crosses the area where I would expect to see movement if the pulley was damaged. Since the line was continuous both before and after the test, I think the pulley is OK. If my reasoning isn't correct, please let me know.

Does it still charge after it returns to idle speed? - Yes. I had not checked for that yesterday, and I'm surprised to see that it does.
Make sure the regulator is correct for M271. Its BSS not LIN bus like a M272. - I don't know whether the voltage regulator on the replacement alternator is correct. I bought it on Amazon, and I have seen mistakes in Amazon listings. The voltage regulator I used on the original alternator (which tested good at the alternator shop) is part number 003-154-98-06. I've searched for that part number on several web sites and it is the correct part number for a 2005 C230. I bought the replacement voltage regulator at the local Mercedes dealer (they matched the Internet price.) I have worked with the parts specialist several times and I think he has considerable expertise. For example, when I ordered the voltage regulator he asked whether I had a Valeo or Bosch alternator. I know he could have made a mistake, but I have more confidence in him than I do in Amazon.

I'm wondering whether swapping the original alternator with the replacement voltage regulator should be the next step. I have tried that configuration before, but I suppose it is possible that I did not install the new VR correctly.

 

003 154 98 06 is the correct regulator for your engine. So now that your alternator is charging you need to check whether the regulator on the replacement alternator has the correct part number.
post the regulator number from the replacement alternator. It may not have a MB number on it. Then post the bosch number I think it will start with F 00M xxx xxx we need to compare those numbers

 

Thanks. I should be able to do that tonight.

 

I reinstalled the original alternator with the new voltage regulator. The Bosch number on the replacement voltage regulator is F00M 144 147. The Bosch part number on the original voltage regulator is no longer legible.

New Voltage Regulator - F00M 144 147


Original Bosch VR - I cannot read a part number

This original alternator/new voltage regulator combination immediately starts charging without revving the engine. Unfortunately, the voltage reading on the dash fluctuates between 14.0 and 14.1 volts and then the alternator/battery warning light illuminates. I cleared the code, but it returned a few seconds after I started the car. Jake's "cold start" videos show that an undamaged charging system would be reading at 13.4-13.6 volts at idle. I'm concerned that if I run the car as it is, I will overcharge the battery and cause another problem.

At this time, I think I have a good alternator/voltage regulator combination. (I am planning to return the new alternator to Amazon for a refund.) Should I turn my attention to the wire that connects the voltage regulator to the ECM?

Again, any suggestions are welcome. I think I am getting closer to a solution, but I am obviously not there yet.

 

What was the code that was set?
Voltage too low?
Voltage too high?
Space Aliens have taken over your charging system?
I'm bored, I'll set a random code to screw with the driver?


You need to fully charge the battery on a battery charger, before you can go around guessing what the charging voltage means.
When charging a battery, voltage and current are tied together. As a battery gets more charge, then the voltage goes up - assuming no heavy loads and constant vehicle load.

Fwiw, the only place I'd semi-trust a voltage regulator from is RockAuto. Otherwise, welcome to the very massive world of counterfeit automotive parts, and playing Russian Roulette with the stuff you buy.


So, you're saying the brand New Bosch Alternator is bad?
If so, you better be 1,000% sure before you return it to Amazon. Amazon isn't some place run by one half-drunk person.
Amazon will know who gets your returned alternator. If that person returns the alternator back to Amazon and says that the alternator is bad, that goes on your permanent file.
Do that too many times, and you're banned from Amazon for life. Btw, the same goes for ordering stuff, and just returning it "way too many times" (even if the items are never unopened).
Major chains no longer just ignore people returning bad/damaged goods.


Good Luck!

 

I bought the voltage regulator at the Mercedes dealer. I think that reduces the probability of a counterfeit part. At this point in the repair process I am ready to accept that anything is possible.

Do you think there is any risk of damage due to overcharging if I drive the car about 20 miles? I don’t want my car to go up in flames like the cars in the pictures you posted.

I read the code with my iCarsoft it was 2062. It wasn’t in the iCarsoft database, but that the same code as I read with the Star system. I will set up the Star system tomorrow night and confirm that it is the same code.

Thanks for the tip about Amazon returns. I don’t track my return rate, but I cannot recall the last time I returned a purchase. I don’t want to be banned for life.

 

MB Dealers sell the regulator? Cool!
Then, imho, the chance of it being a Genuine Bosch part is ~99.99999999%.

Amazon won't ban a person for one bad return. Amazon will if they see an "above expected bad return rate". There's a lot of the interweb now about Amazon banning people and why.
It's like Walmart. If someone is returning $500 of clothes a month, and they buy $1,000/month, then that's a high return rate, and one that will trigger a review by a person.

When the LIN-bus is not plugged in, then the default voltage output is ~~~13.5 -> ~14.3v.
Note, the exact value is chosen by the vehicle manufacturer, then the LIN-controller is one-time programmed with values (like manufacturer ID).
Note that for the TC80310, from the factory, the default value can be either 14.3v (page 2), or 13.5v (page 29).
https://www.nxp.com/docs/en/data-sheet/TC80310.pdf

So, even on the same model alternators (made at different times), they may have different default values.
MB, and Bosch, change values as they see needed.


20 miles is fine for that charging voltage.
The battery should be able to handle the voltage/charge. But, I wouldn't push my luck with an old battery.
Fwiw, the current that a battery takes at a specific voltage is a little involved.
For a specific battery, it may take a lot of current, or it may take only a little. It depends on the percentage charged, along with the "wear" of the battery, the temperature, and a few other variables.

The W203 04+ C230 alternators do have a LIN-Bus. Iirc, so do the earlier W203 C230s.
Even today, MB uses the same LIN connector for its alternators.
LIN was created in the late 90's. Then, it got certified as an SAE and ISO spec.

LIN bus history
1999: LIN 1.0 released by the LIN Consortium (BMW, VW, Audi, Volvo, Mercedes-Benz, Volcano Automotive & Motorola)
2000: The LIN protocol was updated (LIN 1.1, LIN 2.2)
2002: LIN 1.3 released, mainly changing the physical layer
2003: LIN 2.0 released, adding major changes (widely used)
2006: LIN 2.1 released
2010: LIN 2.2A released, now widely implemented versions
2010-12: SAE standardized LIN as SAE J2602, based on LIN 2.0
2016: CAN in Automation standardized LIN (ISO 17987:2016)

Good Luck!

 

Btw, one of the definitive books on batteries.
It's only ~1,500 pages. Quick read. ;-)

Linden's Handbook of Batteries
~$130
Hardcover: 1,456 pages
Publisher: McGraw-Hill Education; 5 edition (May 16, 2019)
Language: English
ISBN-10: 1260115925
ISBN-13: 978-1260115925
Product Dimensions: 7.5 x 2.2 x 9.5 inches

 

Don't worry about your voltage compared to another car. Your load and battery state of charge differs. Its not a problem at 14v.
have you messed with the coding in the ecu at all?

 

No

 

Check the wire from the alternator to the ecu and from ecu to front sam
for continuity and shorts to gnd.
If you have team viewer on your laptop I can check if the ecu is coded correctly

 

No one wants their car to catch fire...

The MB engineers made a bracket for the w203 (and I’m sure for your awesome w204) seat to hold an extinguisher...

 

If it mounts using the fasteners that attach the front of the seat to the floor of the car, the same bracket should work for a W203 seat and a W204 seat. The seat rails are identical in the W203 and W204.

 

Thanks. I won’t be in the same location as the car for a few days. I will be completing some research on this and I may have some questions. I need to:

1. Determine how the wire is routed from the alternator alternator to the ECU and from the ECU to the SAM.

2. How to use Team viewer. Team Viewer is installed on the laptop I use for DAS. I have not used it, but I am willing to learn. The laptop It is an older model IBM Thinkpad that Jake and I bought on EBay. I haven’t used it on my home network and I need to find out whether it will connect . Here’s a link showing what I have. If someone is familiar with the operation of an older Thinkpad please feel free to comment.

It may take a few days for me to educate myself.

 

There is no need to determine the wires routing. Just take a multimeter and measure it from alternator to ecu pin and from ecu to sam.
for TV you need an Internet connection
Try plugging a lan cable into the laptop and start TV to see if it shows ready to connect.
otherwise send screenshot of variant coding

 

I am preparing to return to work on my alternator problem and I want to have all the information I need available before I start. I found this video which shows the procedure for removing the connectors to the ECU starting at about the 2 minutes 15 seconds point:

I have been searching for information showing:
1. Which pin on the ECU harness holds the wire to the alternator?
2.Which pin on the ECU harness holds the wire that runs to the SAM?
3. Where does the wire from the ECU connect to the SAM?

I will keep searching but most of sources I’ve found have not been helpful.

 

I've been using my limited knowledge and attempting to follow Russell's instructions to "send screenshot of variant coding."

My first test was to read the fault codes which are shown in this photo:


2062-02 Is the code I've been reading out since I damaged the alternator cable. 201D-001 (P0420) is the catalytic converter problem I was attempting to track down when I dropped the wrench and damaged the alternator cable.

Code 2014-002 - Charge pressure too high (P0238) is a new one. An on-line search reveals this description for that code, "Code P0238 is triggered when the intake boost sensor circuit shorts to power or opens completely, causing the signal to the ECM to go way over, or below voltage specifications. The most common failure is the boost sensor shorted internally, or the harness has been shorted on the exhaust manifold." I think this may have been triggered because I ran the car for a while with the alternator producing between 14.0 and 14.1 volts. If there is another possible explanation, please let me know.

I then tried to to identify the data that Russell called the variant coding. The screen shown in the next photo seems to provide some information:


The next screen also looked promising, but when I attempted to read the SCN (Software Calibration Number) I received an error message.


I checked all of the cable connections, and re-ran the test, but the system returned the same error message. I also tried the test with the car running and the car not running. It is hot and humid in my garage and at the point I started to get the error message, the system had been running for a while. I decided to shut down the system and make sure it was not overheating. I will store the components in air conditioned space and make another attempt tomorrow night. The laptop I'm using is pretty old, and that may be a contributing factor. I attempted to install it on my home network last night and couldn't make it work.

am also continuing to search for ECU pin out information so that I can check for a wiring issue between the alternator and the ECU and the ECU and the front SAM

Again, any suggestions for interpreting this information will be appreciated.

 

You need to look under control unit adaptations
Read coding
I will look up the pins to check tomorrow at work for you

 

don't worry about scn number. It will not help you

 

Thanks
I connected the DAS tonight and attempted to follow your guidance. I'm beginning to wonder whether there is something wrong with the old IBM ThinkPad I'm using. Starting DAS yield an odd-looking screen:

Faulty Screen

Correct Screen

After a restart, the correct screen appeared, but I question whether there is a problem I cannot see.

I progressed through the screens and selected the control unit adaptations option:


I then selected control module programming and the system returned this error screen:


Part of the message is in German, but I think it is telling me to restart the system.

When I chose "OK" this screen displayed:

Again, part of the message is in German.

Since I wasn't having much luck with DAS, I connected my iCarsoft and scanned both the ME-SFI and the front SAM. The iCarsoft found the same codes in the ME-SFI as DAS, but it did not have the definitions of the codes. I also found three codes in the Front SAM. B1029, B1030 and one that I did not photograph well and and my photo was too blurry to read.

B1029 is non communication with the climate control, B1030 is non-communication with the Upper Control Panel and the third appears to be non-communication with Ignition Control Module. Several of the web sites I've viewed indicated these codes could have occurred because of a voltage spike. My theory is that shorting the battery-starter-alternator cable could have caused those problems. I cleared the codes and I will take a very brief test drive tomorrow to see whether that helps. I'm not anticipating that it will.

I'm thinking of shipping the multiplexer to Jake so that he can verify that it works with his laptop. Everything worked fine when I was repairing my front SAM and initializing my TPMS system. I'm surprised that the system has suddenly become unreliable.

I'm hoping that checking the communication between the alternator, ECU and SAM using Russell's information will yield some clues.

 

Firstly the wiring you posted in post 2 is valid for your car. You can use that for testing.

You will get an error in DAS complaining about can't connect socket to listener because you started DAS standalone and not via xentry
but just click OK to continue.
When you get to the screen online (networked system....) just press F6 for offline programing
I will get you the password when you ready.

Last but not least... you mention you repaired the front SAM? What exactly did you repair? Because a faulty SAM can also cause your alternator light issue!

 

Please.
I have no need for the multiplexer, and, this is why we bought it.

As far as I know, there is NOTHING I can do right now to enable Distronic with my manual transmission...I just get to watch it come fully online before the plugs fire! Ha!

 

What has your problem got to do with this thread?

 

I replaced the front SAM before I damaged the charging system. The front left turn signal didn’t work and after some trial and error I was able to confirm the problem was due to a faulty front SAM. I found a used SAM from a 2005 C230 with an automatic transmission. I had to change the reverse gear code In the SAM from "Single Rod Gearshift" to "Old transmission (203) before model refinement." Before I made the switch, the reverse lights were on all the time except when the car was in reverse. Here’s the whole story if you are interested:SAM Replacement

I was not having a problem with the replacement Front SAM before I damaged the wiring.

I have time tomorrow to work on the car. Thanks again for your help. I am a slow learner, but I am persistent.

 

Okay no problem. I know about that reverse light issue! Let's look at engine ecu coding once you have checked the wiring
good luck