Since the Alternator is still charging at 14v – I now am thinking it might be worth renewing the Voltage regulator on the back of the Alternator. It’s a cheap parts and I guess it could be faulty or throwing false ‘No Charge’ codes to the car.

Fully charged Battery went in this morning & it’s still exactly the same..... so it definitely is not the Battery.

All I can think of is to try the new VR on the Alternator unless anyone can advise on what else could be going on here

 

The best way to remedy this problem is to pull the codes.
If you have a fat wallet, try replacing the BCM (battery control module), it is often the source of many electrical issues

 

I know this is going to sound odd, but you might check for a second battery anyway.

My wife has a 2006 E350 facelift model, and it still has SBC brakes and the second battery.

Some assume that a facelift model means no second battery, and I have proof in my garage that such is just not the case. It may be unlikely in your case if yours is a 2007, but stranger things have happened.

 

That's really not unusual, different things happened in various years. The 2006 model still had SBC brakes and and the balance shaft problem. It goes by year, not whether it was face lifted or not. SBC was gone in 2007 and so went the 2nd battery.

And yes, for battery problems, it's usually alternator, voltage regulator, battery control module and lastly loose terminals, connections. Also voltage isn't a good indicator that the battery is good. Only way to tell is to get it load tested. Most auto parts stores like Autozone, Advance Auto and others will do it for free.

 

Thanks for the info guys- I have checked the car & for sure it has no second battery.

Guven that- I presume it does not have a BCM?

I bought my own Star setup today so next week I'll be able to properly pull codes from the car. Always meant to invest in my own Star setup- now seems like a good time!

All battery connections are clean & tight I checked that too last night.

I suspect the Alternator / regulator is throwing false no charge codes. Hopefully Star can confirm that or lead me to a module that's faulty.

 

Facelift 'bcm' is small little box on/near battery terminal/pole.

 

Thanks – I seen that item & thought it looked like some sort of data sensor. Perhaps it is giving bad readings to the car. I have spoken to a local used Mercedes parts supplier I know and he is happy for me to go over on Monday and swap the parts out such as the BCM & Sam Module. No fix no charge. Pretty good of him to offer.

But then again my Star setup is coming mid next week so I’ll see how things go I might just wait until I get the Star on it.

 

Ok so I got the Star system delivered today & tried to fumble my way through it.

There were 2 fault codes stored-

9313 Interior CAN Bus: Short Circuit in CAN lines / CAN Bus Low Short circuit to Ground
9311 Interior CAN Bus: CAN Bus High Short circuit to POS

And another huge list of faults but I presume those are as a by product of the above or old stored fault codes maybe. I have attached all info I could get from the car.

So what next? I think i’ll try to pull the mats etc in the front interior and inspect the CAN Modules for water ingress etc.

I would really appreciate feedback on the codes / data from someone more knowledgeable on w211’s than myself!

 

Just in from more tinkering – I did the following

Removed and cleaned the thick red wire terminals at a module in the boot. This is something to do with the battery but not sure exactly.

Replaced the BCM which is part of the Negative Terminal assembly on the battery

Removed both front mats / trim and checked for sign of water ingress – none whatsoever. All wiring was dry & clean.

Swapped out the Battery for one that’s been one the charger for several days on end. Thought it wouldn’t do any harm to try.



All of the above made zero difference. Car still lights up the dash red as soon as the ignition is turned on. And most of the car still disabled – no fuel or temp gauges & no mileage displayed still.

One thing I did notice is some water ingress in the boot of the car – at the spare tyre well. I presume this is from the new Towbar install of last year but is very minimal & I’m not sure that would have anything to do with the issues now.

 

Final bit of info for this evening-

When I try to access the modules in turn for fault code reading etc the errors attached in the images keep appearing.
So I can get nowhere. Seems all the car’s CAN systems are FUBAR’d

Is it possible the main front SAM module could be the culprit here? I could swap it out tomorrow to try?

 

The 2 fault codes mentioned above do not re-appear since they were deleted. (No new codes at all) So without any clear way forward I suspect some of the 2 following cases is causing all the CAN errors-

Alternator Voltage Regulator is giving no data feedback to the ECU even though it is charging. So I will order a new Bosch item today and fit that tomorrow night.

SAM module up front in the engine compartment (RH) is faulty and not powering most circuits up. I have been told this is a very common failure by a local wrecking yard and they sell them regular. So I will swap that out too and see if the car behaves itself after that.

 

SAMs are programmed per VIN to each car's options so take note of that when using the MB Star to program the SAM you put in.

It is perplexing. I hope you find this ghost in the machine.

 

Thanks for the info Noodles- I did not know the SAM must be programmed by VIN. I got a loan of both a SAM and Central Gateway module today. So tonight I swap both of those out & see if it makes any difference

 

You are welcome. The central gateway also needs to be version coded by vin. There should be info about it with the WIS part of the MB star system you got.

 

Well I fitted the SAM Module – no difference whatsoever. Dash still lit Red all the time and the headlamps etc still come on with the ignition even though the switch is at 0. + Fan running etc so still the CAN limp mode thing it’s doing.

I did also replace the Central Gateway - **BUT** the spare one I had was the wrong part number. The casing was also black whereas the one fitted in the car was a silver case. The plug was the same so I tried it anyway. It seemed the car did not like it since the headlamps were flickering all the time. Perhaps this is because my car has Xeons and the module did not support that. However it was interesting that that module had an impact on the headlamp circuit. (This is one of the circuits on the limp mode – No CAN data)

For now I put both original modules back in & ill return the spares tomorrow. I would like to get a matching silver Central Gateway just to try that out.

Tonight I also removed the Alternator and it will be dropped off at a specialist tomorrow. The correct Bosch regulator will arrive with them tomorrow so they are to fit that and bench test the alternator before giving it back to me.

This may be unnecessary since nothing yet has pinpointed the alternator but I do want to rule it out now too. Plus with 180k miles on the clock it can’t hurt putting a fresh VR in there.

After that I don’t know what to do. I am running out of free time to work at this car so I’ll have to drive it as is next week

 

Reading up more about the N93 Central Gateway it seems to me it's the culprit.

My odometer is blank- that & the service information is stored on the central gateway. The headlamps are also on constant and it controls them too among various other systems.

The wrecking yard also said when aux fans run wild it's usually the central gateway.

So I'll get the part number off the old one tomorrow then price a new one & check prices / availability of used ones. Then decide which route to go.

Then I'll need to figure out how to code it with DAS maybe try to take the old info off mine if possible.

 

Today I got the Alternator pro rebuilt. They fitted all new bearings, slip rings & a new Bosch regulator and bench tested it. No good- car is still just the same. At a total cost of £54 the Alternator re-build was cheap and at least I know it’ll be good for the rest of the life of the car practically.

So from there I re-focused on the Central Gateway Module. I found used ones in abundance online so I have one coming next week with exact matching part numbers. I will figure out the VIN coding if the car doesn’t want to accept it as is. The version of Star I have allows for offline coding so I can do that myself so long as I can figure out how to.

Looking at the module already in the car the paint markings on it would indicate it has already been replaced with a used unit in the past. And I decided to perform a ******* test on the Central Gateway by removing it from the car and taking it for a drive – it’s just the same! The mileage info is stored on the central Gateway so since my odometer is blank that was the first clue. Knowing now that removing it makes jack shit difference to the car – confirms with a reasonable degree of certainty that it’s defective.

I’ll update next week when I get the replacement Central Gateway module fitted

 

You are correct, those markings do look like the CGW has been replaced with a used part. That is not a bad thing.
However if the CGW was really toasted then getting other control units that all "talk" to the CGW should not communicate to the CGW. (disclaimer: I have seen bad CGWs let MB star into other control units like the AAC and airmatic.) However no programming was needed. It was just a quick test or turning off the SBC to do brake jobs.I know you do not have SBC, but I was using that as an example. Generally speaking CGW failures are not common. I wish I had more to offer for advice.
Can you bring up other control units and test them with the MB Star? If you can I am not sure the CGW is at fault.

 

I can't get into most units in the car at all Noodles- Star throws up that error in the pics previously. (No voltage) So I can't communicate / read fault codes with most of the car's modules.

So the Central Gateway must be shutting off most modules & putting the car in Limp mode.

The test of removing the central gateway & starting the car up is pretty significant I think. If it were functioning at all I would have expected something to change in the cars behaviour but it was identical to before. Suggesting that module is not functioning at all.

Star did also point to the Central Gateway being faulty at the top of previous screenshots I posted. I do not know if those are historic codes- and since I cannot communicate with most modules I can't get in to clear codes & see if they reappear which sucks.

but I reckon I'm onto something with the Central Gateway- fingers crossed!

 

Screenshot attached. 3 pages of CAN errors follow that screenshot! But the Central Gateway is right at the top.

Again I cannot be certain those are current codes and not stored ones? I am not very familiar with how Star works but I'll learn

 

That screen is displaying ALL fault codes possible for your vehicle in DAS & their definitions, not necessarily the ones stored or current. This video link demonstrates how to save a partial EEPROM dump from TCM control unit (as an example) in DAS which can then be used to flash to EEPROM of a replacement: https://youtu.be/r2157mA-6y8 This is how a control unit foreign to your VIN can be cloned to replace a failed one I believe (offline SCN coding). Unfortunately, EEPROM dumps can only be saved like this in DAS when control units are working & communicating properly via OBDII. To get EEPROM dump from a failed control unit will probably require a JTAG or similar device & s/w such as Winexplorer to read & save EEPROM dump of failed unit via JTAG. EEPROM dump from a failed control unit should probably not be used to flash a replacement as it could contain errors iin code that led to original unit's failure. A website you might find useful to get help with learning STAR diagnosis is mhhauto.com

 

Reading over the posts with the pics I am seeing it as you have now described. The CGW or power to it is a problem.

 

Thanks for the info PSDCamperVan - & for the Video / Site link. I will join that forum later it will be very useful for me.

So there are 2 Scenarios here as I see it-

A: I install the replacement used Central Gateway module. Some systems come out of limp mode indicating the old unit was at fault but coding is required to include all of the Vin specific options on my car. Or it just works 'out of the box' but that's a long shot I know. As for the coding - so long as I know the module is making a difference I could find a specialist to carry out the coding for me if I can't do it myself to complete the install.

B: Replacement Central Gateway module makes no difference and I'm back to square one. Then I will have to further investigate where the power is lost in the car.

What I have noticed is most of the symptoms are actually within the cluster itself & steering wheel buttons non functional. For example I initially thought the turn signals did not work - but they do. They just don't show or click inside the cluster. The steering wheel controls for the radio don't work- but the radio does just fine.


If the Central Gateway does not make any difference I will compile an exact list of what systems are non functional and maybe try WIS / wiring diagrams to find the likely culprit.

The alarm also went off last night and wouldn't respond to the key. So I jacked it up & unplugged it - bizarre. Impeccable timing for a siren failure- or related to this fault- I'm not entirely sure.

 

The replacement Central Gateway module has not got here yet but I have been doing some more research & found some great info online

Best bit so far is this-

http://www.mercedesdriver.ru/storage/301.pdf (I presume this is from WIS perhaps I will have a more up to date copy on my own new system)

The particular 2 pieces of interest are-

Page 8, regarding the system diagnosis page- it states "Puts suspicious components in order of likelihood". Remember the Central Gateway was top of the list before on a screenshot I posted?

And page 7;
CGW module replacement
"-CGW modules attempts to adapt to vehicle control modules"

This sounds like it 'might' be plug and play but I know this is optimistic.

I was trying to plan ahead with what I would need to test the can bus system if the CGW does not cure the problem, then found this excellent article-

http://www.benzworld.org/forums/r230-sl-class/1988297-230-can-bus-how-test.html


So anyway- ill see what happens when the replacement CGW gets here & update after that.

 

OK, so the CGW is still not here (Surprise Surprise) but I did figure out how to code it. See the PDF attached – each item is available to view and I now have a record of my car’s setup. So when the replacement used CGW eventually turns up I intend to fit it, connect Star & Code it to match this same configuration. Then see if anything changes – but hey it might make no difference at all to the current faults.

PSDCamperVan – you were correct I was reading all the codes – not the ones relevant to this car.

On the attached PDF the information lists the actual Fault Codes relevant to my car currently.

It’s frustrating because I cannot get time to properly delve into trouble shooting this car right now & I’m forced to drive it as is which is not good. I do hope to set aside a few Hours this Saturday to delve into the car’s CAN network if the CGW does not cure things.

In the interim I would be most grateful for your opinions on the attached Fault Codes / Data

 

So it wasn't the CGW. I started removing the CAN connectors and found one that when removed let the ABS & ASR function again AOK.

The faulty module was taking down the whole interior CAN when hooked up.

Turns out this is actually the cluster itself. It does have an impact on the function of the headlamps and control stalk. Not only are some of the gauges faulty but it's messing the whole car up when connected.

Very deceiving this one! I'm very glad to have found the problem. To be 110% sure I will check the IC plug in the car for power & earth when I remove the cluster on Tuesday night. If present then it's dud for sure.

I'll send it off to get repaired so I don't have to get into coding a replacement cluster.

 

I have sent the cluster to BBA reman today so I hope it gets repaired in the next few days.

I don't know how easy or hard the cluster is to repair - BBA offer a lifetime warranty for a reasonable price so it is what it is.

I'll update if that cures it

 

 

Finally got the cluster back today. Car is fixed- miles displayed & everything working 100% perfect again. Just so you know BBA was £180 odd for the repair and return shipping etc. Lifetime Warranty included so if it does it again in the next few years the repair will cost nothing. I intend to hold on to this car so that was the best route for me. Could have bought a used one cheaper but then it would have needed coding & the miles corrected

So besides the run around to track the fault down I'm glad it's fixed & I didn't have to concede defeat to the MB dealer.

 

Finally got the cluster back today. Car is fixed- miles displayed & everything working 100% perfect again. Just so you know BBA was £180 odd for the repair and return shipping etc. Lifetime Warranty included so if it does it again in the next few years the repair will cost nothing. I intend to hold on to this car so that was the best route for me. Could have bought a used one cheaper but then it would have needed coding & the miles corrected

So besides the run around to track the fault down I'm glad it's fixed & I didn't have to concede defeat to the MB dealer.

Hi, I have a 2004 E320 4Matic Wagon and am having problems similar to what you had in 2016 though the CAN BUS short circuit is only on the Low Bus apparently so I have erratic operation. You traced your problem to the "Cluster" - are you rereferring to the "Instrument Cluster" or some other?