Hi guys, just scanned my W204 C180 1.6 kompressor with vehicle diagnostic machine and got the fault code communication with the starter or alternator has a malfunction..

Tried to do research but it's not working, could I please know the possibilities of causes and the sequence of trobleshooting on parts?

Looking forward to you guys kind & experienced opinion.

 

I have same error codes P3260 on my W204 1.6l Kompressor Blue Efficiency. 6speed Manual.
i replaced a faulty Valeo Alternator with a Bosch 120A unit.
At startup alternator voltage is about 12.3v but when I Rev to 2000rpm it goes to 14.2v and stays even when back to idle. until I turn off the car and start again.

 

Your alternator is proven working, some time. I know for fact this does not mean all the time. It's controlled by the ECU that sometimes can ignore its ALT.

Can you use your scanner to open the related modules available.
I doubt starter shows up with a simple solenoid actuator

Tell me: is this fault STORED or CURRENT ie.
1-- Active or
2- Transient
(i believe #2 here)

Where this is going is....
I would consider REBOOTING your whole car system. Prior to that, see that steering angle does not need relearn afterwards or be ready for it

 

Thanks very much for your response,
The error is both Stored and CurrentCurrent.
Alternator was also tested in my W209 with same M271 Engine and it works perfectly from startup.

 

All right, CURRENT means it's not a transient glitch. It's more of a solid fault.

> Both starters and alternators work good but the ECU indiscriminately complains about both.
You have replaced ALT, I don't know about any starter reporting. I know how starter brushset go bad but that is usually a parking lot surprise.

> Can you shows us your list of live Modules ?

> Can you get into the ECU data and look at related fields... something may become obvious from bad/missing data?

 

Good Day,
Thanks very much for your support.
Attached is a clip of the generator module in the ECU

Ignition ON

Idle speed after starting.

After revving the engine and back to idle speed
at startup through revving.

 

You have captured evidence that confirm this problem with the generator.


Voltage and Amps outputs should track together...

"Calculated Amps" is a way of saying Amps from alternator internal measurements, not Amp measured by the battery sensor.

So ECU and ALT are not communicating well is 100% confirmed as the problem.

Now you can concentrate on WHY and WHAT to do about it.... such as:

-- Inspect ALT control LIN wiring

-- Measure GND between Motor and Chassis

-- Replace ALT regulator to match VIN (not a replacement match) ???

I think this ALT LIN issue is likely the way the ECU-ALT LIN Bus was setup in factory.
LIN depends on one single noisy wire for serial com (unlike CAN Bus). The 0/1 thresholds got setup with improper levels. It needs to be reinitialized properly with Xentry.


Right now what is saving your day is the ALT internal regulator is smart enough to regulate car voltage. This backup regulation mode is one of ALT functions.

A great many MB vehicles suffer with this LIN Bus issues caused by poor GND reference connection on MB painted GND posts.
Say... ALT and ECU use a different GND reference not common to each other.

>> Go ahead now, clean the ECU GND connections in footwell area (while BATT disconnected).
🤞

 

Thanks Very much, I will do this and reply back with results.

Thanks.

 

The every day shortcut is to get your car into a MB Specialist independent shop that has use of a Xentry-Star MB tool.

Go ahead and replace regulator to the latest updated MB part INCLUDING THE PROCEDURE TO SCN NEW PART.

The Xentry massage trains these parts to talk to each other. Right now they can not. First mariage of these parts was unsuccessfully done.
Call this procedure a sort of unlocking by authorized MB Tools.

>>> No joy without fresh reprogramming ECU LIN device.

 

Good Day friends,

Problem solved.

Action taken.

Got a Compartable voltage regulator and installed in the Bosch Alternator. Error has been cleared.

Once the engine is started the Alternator starts charging immediately at idle speed.

Thanks very much for your support. It was really helpful.

 

Very nice. twice in the past few weeks I started the car and proceeded to pull out the driveway and the dash light up red with a battery symbol. I backed up and parked, turned the car off and waited a minute or two then started it back up and no more message, nothing stored on the dash under messages either. I'm assuming the voltage regulator may need replacing. Think mine uses the Bosh F00M144151, found it for $30.95 but its not in stock so just waiting.