Rear SAM Symptoms
Super Member
Joined: Sep 2015
Posts: 639
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From: Cleveland OHIO
01 ML55AMG 04 ML500 03 ML350 08 ML63AMG
Thread Starter
Senior Member
Joined: Aug 2017
Posts: 393
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From: Ontario, Canada
2006 ML500, 2008 ML350
This is very strange, my message I placed here (and hit the Post) more than a week ago is not here! Sorry for the oversight.
Here's what happened:
Before I removed the Front SAM, I ran the code reader once more, and this time no code was registered. I checked the SAM, there was no sign of moisture, rust, or debri of any kind. I checked under driver seat, as well as the rear SAM location, same again, no sign of moisture, rust,....
The engine shut off really scares me. I'm thinking maybe it was because I was running the code reader with the engine running. Could this be the reason for the sudden engine shut off?
I've been driving the car since with no drivability issue, but always on the lookout.
Here's what happened:
Before I removed the Front SAM, I ran the code reader once more, and this time no code was registered. I checked the SAM, there was no sign of moisture, rust, or debri of any kind. I checked under driver seat, as well as the rear SAM location, same again, no sign of moisture, rust,....
The engine shut off really scares me. I'm thinking maybe it was because I was running the code reader with the engine running. Could this be the reason for the sudden engine shut off?
I've been driving the car since with no drivability issue, but always on the lookout.
Thread Starter
Senior Member
Joined: Aug 2017
Posts: 393
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From: Ontario, Canada
2006 ML500, 2008 ML350
Yes. Oddly enough there's no code at all. So it's baffling to me what caused the incident explained in my original post. Computers going berzerk? Engine shutoff is the scariest
Thread Starter
Senior Member
Joined: Aug 2017
Posts: 393
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From: Ontario, Canada
2006 ML500, 2008 ML350
Even when the engine is running? If so, it can happen while driving. That's exactly what I'm scared of. Should I replace the SAM with a new one?
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From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
If you are driving the car and it loses communication with the I.C. the eng. will shut down.
All the codes you posted before were in the I.C., correct?
Were there any codes in either SAM?
All the codes you posted before were in the I.C., correct?
Were there any codes in either SAM?
Thread Starter
Senior Member
Joined: Aug 2017
Posts: 393
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From: Ontario, Canada
2006 ML500, 2008 ML350
The larger list was for the Front SAM, the latter list was for the Instrument Cluster.
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Thread Starter
Senior Member
Joined: Aug 2017
Posts: 393
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From: Ontario, Canada
2006 ML500, 2008 ML350
MBWorld Fanatic!
Joined: Oct 2011
Posts: 7,107
Likes: 765
From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
Thread Starter
Senior Member
Joined: Aug 2017
Posts: 393
Likes: 10
From: Ontario, Canada
2006 ML500, 2008 ML350
Thread Starter
Senior Member
Joined: Aug 2017
Posts: 393
Likes: 10
From: Ontario, Canada
2006 ML500, 2008 ML350
In reading this sheet about CAN I noticed mention of Circuit 15. What's it about this circuit that it's mentioned so often. Even on the code reader there's a specific test for this circuit.
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Joined: Mar 2006
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From: San Jose area
'19 E63S sedan
Circuit 15 is positive battery voltage, switched (15R is on in positions 1, 2 and 3; 15X in 2 only). Circuit 30 is 12V+ continuous. Circuit 31 is battery negative (never switched). These are DIN standard terminal codes.
Thread Starter
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From: Ontario, Canada
2006 ML500, 2008 ML350
MBWorld Fanatic!
Joined: Mar 2006
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From: San Jose area
'19 E63S sedan
The DIN standard only defines 15 (+ through ignition switch). But in modern cars like these, there are many variations on that. For instance, when you turn the key off the radio continues to play until the door is opened. That's 15C, I believe. SAMs enable a dizzying range of variations on "switched power."
Newbie
Joined: Feb 2020
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2008 R350
Gentlemen, battery voltage when a veh. is idle should be 12.7 volts. And at 12.4v it should not prevent starting nor should it not shut the eng. down, unless there is an alternator problem.
Where did you jump start the truck, at the main battery or from under the hood?
Here is a PDF on the failing steering wheel buttons.
Where did you jump start the truck, at the main battery or from under the hood?
Here is a PDF on the failing steering wheel buttons.
Super Member
Joined: Sep 2015
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From: Cleveland OHIO
01 ML55AMG 04 ML500 03 ML350 08 ML63AMG
That's what I'm saying. This always gets annoying when you read folks leading other folks down the path of nowhere. This isn't a battery related problem, if it was ALL problems would be resolved once the car started getting alternator power. And to be honest, I've had Mercedes that still cranked and started with 11.9v. I wish we could bypass alot of these types of suggestion and get to the meats of help in these forums. These Mercs are still logical, as are we. It doesn't answer any questions to say "hey these things are sensitive to voltage, who knows what could happen". If there's enough power to crank the starter, (even jumped), and the little electrical problems are still there, it's not the battery, move on. Next would be finding what controls the items that are messing up, the Sams. Check the fuses , mainly if the feature stops working altogether, and then get ready to fight the real fight. Get a scantool and start diaging the Sams. Go-to live data and press the buttons physically to see if the system is "hearing" the command. Go-to activations to manually activate the things that are not working. If there's anything magical or questionable going on at this point, we know it's gonna need reprogrammed or replace. Don't mean to sound harsh, or rude, but alot of threads fall off unanswered and when you read the posts , there was just alot of unrealistic "ty this" posts, and so the op ends up off to a dealership. End of rant lol.
I got problems with my 08 ML63 left taillight acting up, rear gate does not open or close, radio light is dim, rear left door lock. i suspect its my rear sam. but i actually opened it up it dont show any water damage at all.
so i guess wires are shorted somewhere. wonder how am i going to find the problem
Newbie
Joined: Feb 2020
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2008 R350
If the basic strategy of diagnosing doesn't work, then on these older cars you can do what the dealer does, but on a lower scale. If you truly suspect a Rear Sam, goto a junk yard and get one. Here, in Texas, they're super cheap, cuz "non Benz/BMW" yards just call them "Module-not Pcm" some even call it a "body control module". Either way both equate to about $35 here. And if you can't find one there, move up to the next level of yards. They're not even painfully specific on those modules, as my Rclass w251 has the same rearSam as w164, which I believe is the Ml. I say a junkyard module bcuz most of these modules control lots of things in the car, and it's unlikely that even another BAD module will display the EXACT same problems. So if you put in a donor Sam and Any of your problems are fixed, even if other problems arise, you'll know your answer. Then you can decide to get a new Sam or internet, ect. Most yards will let you exchange as well. This IS AFTER you've tried the other diagnostic methods.
Super Member
Joined: Sep 2015
Posts: 639
Likes: 36
From: Cleveland OHIO
01 ML55AMG 04 ML500 03 ML350 08 ML63AMG
If the basic strategy of diagnosing doesn't work, then on these older cars you can do what the dealer does, but on a lower scale. If you truly suspect a Rear Sam, goto a junk yard and get one. Here, in Texas, they're super cheap, cuz "non Benz/BMW" yards just call them "Module-not Pcm" some even call it a "body control module". Either way both equate to about $35 here. And if you can't find one there, move up to the next level of yards. They're not even painfully specific on those modules, as my Rclass w251 has the same rearSam as w164, which I believe is the Ml. I say a junkyard module bcuz most of these modules control lots of things in the car, and it's unlikely that even another BAD module will display the EXACT same problems. So if you put in a donor Sam and Any of your problems are fixed, even if other problems arise, you'll know your answer. Then you can decide to get a new Sam or internet, ect. Most yards will let you exchange as well. This IS AFTER you've tried the other diagnostic methods.
well after playing around with all them wires putting everything in place and checking with my tester when i put everything together my taillights started to work right i get nomore errors.
only problem left is my Power liftgate doesnt go up or down on its own. softclose does work. i wonder how can i pinpoint that problem.
Newbie
Joined: Feb 2020
Posts: 3
Likes: 2
2008 R350
Yes the Rear Sam should be programmed to correct tweaks that are specific to your Vin. You still have to do that. The idea here was to verify cheaply if your initial problem was related to the Sam. Certain functions are common across all vins. As for your liftgate. I would, using a scantool, goto the cgw central gateway, maybe even eis. You're looking for a main module that would store the configuration of your car. In that module goto coding and look to make sure power liftgate is enabled. This is just a check. Next goto rearsam, Live data. Some even have a tailgate module. Anyways, you're looking for switches. The tailgate normally has several sensors/switches that need to be certain places at certain times, which allow the liftgate to function. Almost like how a automatic convertible top has micros witches. If you're getting beeps and rejection noises most likely this is the case. If you're getting dead, dry nothing, as in no response at all from the tailgate buttons or the key fob, then first guess would be you're not getting power to that function.... As in a bad fuse or relay. The motors that run the tailgate are 12v, power hungry, so try to activate the tailgate with the car on/engine off and keep your eye on something like the overhead light/reading light. If it goes dim when you try and run the tailgate, there's a good chance the module is doing its job at least past the relay. No dimming would mean the module most likely isn't even trying to run the motor. To get a feel for what I mean lock and unlock your doors while looking at the overhead light. Of course, keep in mind to not totally drain your battery.
Thread Starter
Senior Member
Joined: Aug 2017
Posts: 393
Likes: 10
From: Ontario, Canada
2006 ML500, 2008 ML350
I had the same problem with my ML350, I swapped the module with my ML500 and it worked fine. So I'd say it's the module under the cargo floor. You can disconnect it to see if operation changes at all. I think the soft lock is not controlled by the module. Maybe the module connection is loose, unlikely likely though; it's a pain unplugging it.
Super Member
Joined: Sep 2015
Posts: 639
Likes: 36
From: Cleveland OHIO
01 ML55AMG 04 ML500 03 ML350 08 ML63AMG
Yes the Rear Sam should be programmed to correct tweaks that are specific to your Vin. You still have to do that. The idea here was to verify cheaply if your initial problem was related to the Sam. Certain functions are common across all vins. As for your liftgate. I would, using a scantool, goto the cgw central gateway, maybe even eis. You're looking for a main module that would store the configuration of your car. In that module goto coding and look to make sure power liftgate is enabled. This is just a check. Next goto rearsam, Live data. Some even have a tailgate module. Anyways, you're looking for switches. The tailgate normally has several sensors/switches that need to be certain places at certain times, which allow the liftgate to function. Almost like how a automatic convertible top has micros witches. If you're getting beeps and rejection noises most likely this is the case. If you're getting dead, dry nothing, as in no response at all from the tailgate buttons or the key fob, then first guess would be you're not getting power to that function.... As in a bad fuse or relay. The motors that run the tailgate are 12v, power hungry, so try to activate the tailgate with the car on/engine off and keep your eye on something like the overhead light/reading light. If it goes dim when you try and run the tailgate, there's a good chance the module is doing its job at least past the relay. No dimming would mean the module most likely isn't even trying to run the motor. To get a feel for what I mean lock and unlock your doors while looking at the overhead light. Of course, keep in mind to not totally drain your battery.
But i did some scanning and i will post pics here maybe that will be more helpful and specific.
Sunroof works fine
Rear left door seems to be fine, any ideas?
Super Member
Joined: Sep 2015
Posts: 639
Likes: 36
From: Cleveland OHIO
01 ML55AMG 04 ML500 03 ML350 08 ML63AMG
I had the same problem with my ML350, I swapped the module with my ML500 and it worked fine. So I'd say it's the module under the cargo floor. You can disconnect it to see if operation changes at all. I think the soft lock is not controlled by the module. Maybe the module connection is loose, unlikely likely though; it's a pain unplugging it.
