Griff2610

Hi guys

I am having an issue with my 2009 w212 e250 and I am looking for some help from the community. I have been getting dash lights flash up ABS ESP run flat inoperative and powersafe functions limited. The lights come and go without warning and occasionally the Speedo dies when the lights flash up to.

I originally thought wheel speed sensor but having plugged in my diagnostic machine (icarsoft mbv1) it has thrown up the following codes.
476100- CAN line has an open circuit or short circuit
627300- fault in control module EZS (electronic ignition switch)
63f900- invalid VIN
694000- fault in control module'A1 (instrument cluster)
6a8200- communication with control module N10 (front SAM control module with fuse and relay module) has a malfunction
P050031- speed sensor 1 has a malfunction. Signal not present
u012100 - communication with ESP has a malfunction



I now don't even know where to start to fix the fault besides whip all the wheels off and check all the speed sensors or take it to MB and get my wallet emptied

if anyone has had a similar issue or knows the best place to start I would be massively appreciative.

griff

Mud

It might be a power failure to the SAM or other control module that's causing all of the various lights and error codes. Your wheel sensors etc may be fine but they can't communicate.<br />Sometimes a single failure creates a number of following issues.<br />I would start by checking power at the fusebox(as) and then verifying continuity of that power all the way to the SAM module(s) and the ECM/PCM.

Griff2610

thanks for that is there any threads on doing that? Or do you know the best way to check?

Mud

I don't know of any particular MB threads on this, you may need to do some digging. IMO South Main Auto on YouTube does a great job on diagnostics and has covered similar on other cars. Maybe of some help as he is very methodical and explains well.
You will need vehicle wiring diagram and fuse box info to know where to verify continuity, and a circuit tester or volt meter.
Hopefully others may add more/better info as well to help you out.

Oda112

Do what Mud said and once you've cleared that I would start looking at that CAN error. Look for the X30 plugs around your vehicle ( driver and passenger door kick pannel) and check for continuity. The wires you're looking for should be a pair of twisted brown/ brown-green wires, the resistance from those wires to the corresponding control units should be 60 or 120 ohms depending on where you are measuring. If any of them have continuity to ground the offending wire is shorted. If you're not comfortable doing this get someone who is experienced to track the short down for you because if you take it to them, the first thing the Stealership will do is start replacing control units. Post more info about your vehicle (engine type, RWD/AWD) and I can post some CAN and fusebox/relay box schematics which might help you.

Griff2610

thanks guys. I will do some looking into it tonight. My Merc is a 2009 w212 e250 manual right hand drive RWD. I cleared the faults and they stayed off for a short while but then the CAN open or short circuit fault came on so it may be that which is triggering all the other faults? Going to check fuses etc.

griff

Oda112

Here's an overall view of how each module connects with the CAN and every other module. There's detailed schematics towards the bottom of the PDF.
CAN shorts can be tricky to diagnose as they usually don't blow fuses, they just annoy the hell out of the computers and make them behave weirdly. It's even worse when they're sporadic faults. Good luck with this, let me know if you need more documentation and share the fix when you figure it out.

Griff2610

thanks a lot for the PDF. I can't get the detailed schematics on the bottom of the PDF I think the one I need is the chassis CAN x30/30 as all the faults I have are within that circuit.

Oda112

Here's all of them. Have fun!

Mud

^^all good info, I would very curious also to see resolution if you're able to solve this. I'm saving these WIS pdf's as well in my MB file!

You asked about the CANBUS errors and yes, as mentioned a single COMM error can mess up a bunch of other sensors.

Essentially even though it's a complicated bunch of electronics, start with simple. Verify power circuit from source to control units - this will allow you to verify wire and connector integrity. Don't forget to check grounds.

Griff2610

After checking all the fuses and can wires for the chassis ( CAN x30/30) I have drawn a blank and can't find any faults within the CAN wiring so the only thing left to check is each wheel speed sensors. Failing that I have found a replacement esp module (same part number as mine). As much as it pains me to say I think that might be the issue as the majority of the fault codes I get say there's a failure within the esp unit, which would also throw up the CAN bus codes due to there being one of the 2 120 ohm resistors in there so if the esp module has packed in then that is going to screw the rest of the components on that CAN circuit. I am also having trouble even accessing the esp control module through my diagnostic tool so it looks like it may have just died a death as the lights haven't been going on and off like they used to, they are now constantly on no matter how many times I clear faults or start the car.
i will keep you guys updated after I check the wheel speed sensors and also if I have to replace the module.
I have seen a few threads talking about the esp module having to be coded to match the vin number is this true?

Griff2610

Ok so after coming straight off a night shift and having been awake for 30 hours there was no way I could go to sleep with this fault playing on my mind so I took it into a Merc Indy garage and hooked up to the STAR they checked everything and solved the problem. They removed the wiring harness that connects to the ESP module and by chance found some of the pins within the harness were a little loose so repositioned them and hey presto all faults have gone and the esp is now communicating properly. So for anyone else having these issues after checking wheel speed sensors etc might be worth getting that harness checked. Although they did say they use a specific tool for fitting the pins and it's not advised to DIY because if you damage them then you open up a whole new can of worms! time for me to go to bed.

thanks again for you help guys!!!

griff

Mud

Excellent!
It's more common for fuse/wiring/connector fail than it is for the actual module to die. Connector pins are the most troublesome as the problem can sometimes be intermittent. The pin tool set is not expensive and makes accessing the pins much easier and without damage. Mine is an eBay versiin that works great.
I had helped my son rebuild a 99 civic engine that had low compression and a bunch of changing CEL codes. Engine ran great after build when it wasn't throwing codes. Took me almost a month of part time looking to finally trace wiring to find 3 loose pin connectors among the dozens at the single ECM for the car.

Oda112

Good job, glad you fixed it. A friend of mine who works at a repair shop was telling me that he has seen similar issues, where pins become loose over time but it usually happens for cars that have quite a few years under the belt. I was hoping 9 to 10 years would still be early for such an error to occur in an MB car. I can only imagine how frustrated one might get while trying to figure this thing out, especially if they're not DIY inclined.

jaymes

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