2005 E330 CDI battery messages on instrument cluster
 

Hey guys,

I had a battery message display on the instrument cluster the stated in RED "visit workshop" and it displayed an image of the battery. Once the reset button is activated the next message that displays is "Battery Protection Conven Temporarily Unavailable".

This happened once yesterday, today it has happened everytime that you start the car. Of course, reset button clears them and the car runs fine. This morning prior to starting I took and instrument cluster battery reading and the standing battery voltage was 11.1. Once the car is running the battery voltage fluctuates between 13.9 to 14.8 volts.

I put my fluke meter across the battery terminals in the trunk and basically received the same readings when the car was running, consistently.

I have attached 2 pictures of the instrument cluster displaying the 2 messages.

Has anyone experienced this type of problem?

Thank all of you in advance!

I often get the convenience functions temporarily unavailable message when it's cold outside (on both my cars), especially if the car has been sitting for a few days. That's nothing to be concerned about. But the red message....need to pull the codes to see what's going on.

Sounds like the regulator is failing to me.

On my 642-powered 211 it holds at 14.4 V rock steady.

And 11 V standing is too low, the battery should be standing at 12 to 12.2 V.

I am assuming they used the similar setup on the OM648 powered 211s as the 642 models.

I would not take chances with a parts store alternator, get a real one from the dealer. Yes it's 2x as much but you will likely have problems with one from a parts store.

Or you can try just swapping the regulator if you want. However given the age of the car it's probably due for a new alternator.

These are not standard B+ and D+ alternators, the regulator runs on LIN bus (single wire serial) back to the ECU and the ECU tells the alternator what to do. There is a current sensor on the battery - terminal that provides the feedback to the system for regulation.

My saga from fall of 2019, I ended up replacing the alternator as part of the larger issue with the CAN bus. http://www.peachparts.com/shopforum/diesel-discussion/400578-w211-can-bus-problems.html. The good part starts at post #12

What is the best and economical code reader than I can obtain for these vehicles? I'm going tired of paying the shops for just pulling codes and I have 2 E320 cdis so it would be beneficial to invest in one.

I have the iCarSoft MBII which works well. Other folks like the Foxwell NT510 Elite or NT530. One those should do the trick...they are comparably priced.

Could be battery control module or voltage regulator. Get the Icarsoft. BCM codes will be stored in the ECU and instrument cluster.

I just ordered the IcarSoft scanner from Amazon, I hope it's self explanatory to a degree. Does it tell you how often a code came in and just it just point you in a general direction or does it pinpoint the exact problem?

It's fairly intuitive and self-explanatory. It simply gives you the code and the description. You have to do the rest of the diagnostic work.

Your post says E330 CDI. I am assuming you mean E320 CDI.
The warning is more likely related to the Auxiliary battery.
The Auxiliary battery is used to prevent the starting battery from draining down.
Convenience features are not available until the voltage of the aux bat is above a certain value.
The battery is located under the cabin air filter on the passenger side of the engine compartment.
One plastic nut (10 mm) to remove, lift the filter housing and filter and you will see it in the area below.
If it is an MB branded bat it will more than likely have a code on the top. The code is a date code. usually represented in weeks and year, i.e. 23-14 would be 23rd week of 2014.
The battery control module is in the trunk by the battery. It will monitor the voltage of the battery and determine if it needs to be charged and direct charge as needed.
There are two or three iterations of the control unit. If it has not been replaced it will only charge the aux battery as needed.
They have been known to fail which is why there are a couple of different iterations.
You can put a volt meter on the battery and see if it is getting a charge during operation. Again, that is if the battery voltage is low enough to switch it to charge mode.

Hope this helps

By the way. I also use a MBII iCarsoft. you have to scroll through menus to get to your car but not difficult at all.
You can get right to the battery control module with that unit.

Mine has been incredibly handy from SRS light to many other data points.

I just received my iCarsoft MBII scanner, wish me well, LOL!

this scanner is MARVELOUS!!!!.... How did I live without one!

The following codes were pulled

ON THE SBC
C225e ABS stored
C249f Service Threshold Reached current and stored

ON the BCM
9092 Axillary battery not installed current
9071 relay or signal to component fault stored
9050 consumer shut off stage II stored
9051 consumer shut off stage I stored
9055 terminal 61 signal on CAN bus missing or faulty

Based upon the codes that I am seeing is it reasonable to suspect the auxiliary battery needs replacement?

thanks in advance!!!

Yes, I would replace the aux battery, clear the codes, and see where you stand. FYI you can get a Mighty Max on Amazon for $40....replaced mine about a year ago and no issues whatsoever.

Your bigger issue is the SBC....need to get to dealer to address under extended warranty.

If it were me, I would replace the aux battery, clear ALL the codes (including SBC), and then see if SBC codes recur.

Thank you for this great information

You may not be out of the woods with just an aux battery.

That may be a symptom but not the root cause. "Terminal 61" is short hand for the voltage regulator control lead.

As I said before, these don't use a traditional regulator with the feedback line from the pilot light in the cluster like the older models, this uses LIN bus to the ECU.

The error about Terminal 61 not reaching the CAN bus sounds like the regulator quit also.

Especially since you have a Level I and Level II convenience function shut down, that pretty much means the electrical system is in serious trouble, and the car is going into self preservation mode to try to keep the essentials running. That won't happen just because you have a dead aux battery. My son on his 2008 E320 found out what happens when you get past Level II, the car becomes a potato, since it can't get sufficient voltage to allow the computers to run and communicate.

See if the iCarSoft will let you do an automatic alternator test, that will smoke out a bad regulator.

Once you get the electrics sorted, get it to the dealer as there is a 25 year blanket recall on these 211s with the SBC system.