>170k on original brushes and having electrical problems?
You are really pushing your luck.

 

Oh i have no idea how many miles are on the present alternator ill have to reference the records. I doubt its original.

 

I am wondering what the rating of your battery is. I was still going through issues even after switching out my regulator and had the same symptoms as you.

The days were hot and the A/C would come on full blast. After a few minutes the battery low message would come up and after a while of driving, it would go away. I had a 650 CCA battery in there. After switching to 850 CCA battery, the issues went away. The 650 CCA battery tested good and I swapped it into my E55 and have not had any issues in the E55. My E320 CDI has a higher power radiator fan (850W vs 650W in the AMG and my original fan motor was 600W in the CDI) so that may have contributed.

Some basic fundamental checks would be to ensure the battery post clamps are good and tight and not corroded.

 

According to po records that are available it was last replaced December 2014 at a merc dealer. The one in the car is the oem battery so i imagine its the same one. Not sure if the cdi battery has higher cca or not but it passed the midtronics test at advance auto.

Are we sure the small (sbc) battery wont trigger this warning? Havn't tested it yet but as stated the functions are fine until what i assume is the car diagnosing something and cutting cconvenience in response. Its more like 5-10 seconds after start rather than the minutes you eexperienced.

 

So Main battery checked out fine and is from DEC 14'.

The Aux Battery also checked out OK and had 12.8 V when tested with car off.

The light and lack of A/C now remains on MUCH longer than before. (it's HOT down here!)

If the Aux and Main battery both check out fine that means that the alternator is doing it's job in maintaining their voltage.

So what the heck is left? Control Module? If I get it hooked up to STAR will it indicate what specifically is triggering the lack of convenience features and warning? Or will it be a generic offering?

 

I will repeat one more time.
> 170k on alternator brushes and you still wonder why you have electrical problems.
SD might narrow the issues, but will not point each screw.

 

Voltage is one thing, current is another. You should get the battery load tested, just because the voltage is there, doesn't mean it will be able to supply the current. Loose wires can also lead to low current flow. There's also the voltage regulator and the battery control module. I'd suspect the voltage regulator first, then alternator, then control module. But if you take it to a shop, they should be able to test all that out without using SD.

 

I think you are spot on. He finally hit rock bottom today.

After weeks of ignoring the convenience features it finally struggled to start and the windows barely were able to shut before I limped it home with no power steering and no SBC.

My suspicion is either voltage regulator OR alternator.
I am going to take both batteries out tonight since the rear is definitely close to dead now and have them tested/deep cycle charged at autopwn.

Question: Could the isolation relay have anything to do with this?

I think I can justify doing the following given the age/miles of the car:

Replace either voltage regulator OR entire alternator AND isolation relay.

Does anyone know part numbers for:

Voltage Regulator
Alternator
Isolation Relay

I have 2005 CDI A757117

Edit: would
Regulator: 0031544106
Alternator: 0131545602

be correct?

I'm also seeing 0041540006 for the regulator.... perhaps updated number?

 

Look at my pics in this DIY. I replaced the regulator. It is for 2005 E320 CDI:

https://mbworld.org/forums/diesel-fo...nator-diy.html

 

Right, based on your thread you mention "The part number is F-00M-145-292 or F-00M-145-374 ~$86 on Ebay."

This means you used 0031544106
Which councides with
BOSCH#

F00M144108
F00M144132
F00M145292 *
F00M145374 *
F00M145884
FOOM144108
FOOM144132
FOOM145292
FOOM145374
FOOM145884

What is odd is the dealer parts site i visit show 0041540006 as the correct # which may or may not coincide with the above list. I guess ill know more when I pull mine.

 

Why make a puzzle when ordering from internet dealer gives you full warranty.
http://www.mbdirectparts.com/ is at this time probably best MB supplier.
For strange reason the MB dealers making internet sales come and go, but that is another story.
The guys above might not be the fastest, but good communication and found me rare parts.

 

Thanks for the leads.

p.s there is a giant intercooler pipe blocking the back of the alternator on the cdi....
i assume this must be removed to gain access to regulator...

 

Yep the intercooler pipe was very in the way. 2 hours of taking all intake components later,

 

Did you follow my DIY? IC pipe is not in the way only the radiator hoses. 35-40 minutes from the top of the engine bay and that is to remove the entire alternator

 

On your cdi? Impossible on mine the socket couldnt even line up with the nut. Not even by a long shot.

 

as long as you did not have to remove it via tailpipe...
Each job can be always done in several ways.
Report if your electrical problems are over?

 

Yes 004-154-03-06 is the most up to date number and its on order. Ill report back but judging by those brush lengths i should have good results.
its weird how they wore so uneven.
oh i also have a small oil leak somewhere that i cant track because of the diesel leak from the pump seals that spread the oil leak all over the place including the alternator...

 

The shorter brush looks burned, when the long one would indicate it was not old.
Most likely the short was hang and sparked a lot.
This way or the other, you did not have much left.
Inspect and clean commutator bars.

 

Attached is a picture of both my new and old voltage regulators. The brushes on the new vr measured approximately 5/8-inch, where the old brushes measured a little less than 3/8-inch. My cdi has 135k on it. One less thing to worry about.
Mike T.

 

Calculating 1/8" for final clearance, you went from 5/8 to 3/8 what is about 50% of usable length.
At 135 k the VR was either replaced, or lights were seldom used.
I posted picture of my brushes after 165k in other topic and did not have much sticking out.

 

I had the cdi since approximately 40k miles on it, so I doubt that the VR or alternator was ever changed. I also have printouts of everything the previous owner had done to the car from the MB dealer. The headlights are on at all times. I installed HID's about a year ago and I had another indie (who works for MB) switch the DRL settings to on(?). I must be too easy on my cdi!
Mike T.

 

FINALLY... I've been dealing with this message for a couple of months, checked batteries, replaced aux. battery (bad anyway), but the message always prevailed! Today I came across someone's thread on here that said his cables were loose!! Guess what, I went outside and mine were loose!!! Tightened them and the message FINALLY went away. While I feel like an idiot posting this, I hope it helps someone to check the simplest most obvious things before leaping into higher cost remedies only to find that dreaded message again. All the best!!

 

Absolutely. Start with the simple stuff...and that stuff always looks fine until you do something like yank on the cable and it comes right off the post. And corrosion is an issue, too.

Although it is most-likely unnecessary overkill, when I install a battery, I put those little red and green felt battery terminal protectors at the bottom of the post, take a battery brush and brush the inside of the cable connector clamps, and spray CRC terminal protectant on the terminal posts and the inside of the clamp connectors. Would it work without doing this? Of course. But five years later, I can open the battery compartment and inspect the terminals and connection, and they are still perfect. Do it right and with pride to start with, and you are far-less-likely to have to redo it later.

 

I believe that only applies to regular flooded lead acid batteries. My AGM battery is still pristine even at 11+ years old. Basically they don't really vent gas that causes all that corrosion.

 

Well, you could be right. Like I said, maybe it's overkill.

On the other hand, I pulled the original AGM Mercedes battery out of a 2008 ML350, and the connectors were covered with corrosion so thick I had to chisel it off...