S-Prihadi

Gents,

Always something new to learn.
I like using case studies of members which I find unique and could be dangerous for us and hence I do my own simulated test to see if my engine ECM has the same logic ?
This was the original case study : https://mbworld.org/forums/e-class-w...operation.html

Anyway, I really enjoy doing simulation test to a known problem a member is having.
This is as close as a training we get from our own car and its related computers or Modules in real time.

The test was, REMOVED RELAY R
- Crank engine twice. Surely engine won't crank.
- Turn OFF Ignition and turn ON ignition, CRANK again. I am hoping to register higher Fault count.
- Turn OFF ignition .
- Hook up scanner.
- Turn ON Ignition



First lets discuss the Xentry bug. It is Xentry not wanting to show the N10/1 - Front SAM has a DTC, a stored one until I cycle the Ignition more times and/or I enter directly into the said module,
instead of just using QUICK TEST menu of Xentry which is equal to SCAN ALL modules if in other scanner.

So, this is a DELAY BUG and only for a STORED code and not a CURRENT/ACTIVE DTC, so it won't harm us but it can slow down troubleshooting.

I only knew of this Xentry DELAY BUG because I was first using Launch Creader Elite for Benz and then I do the test again with Xentry. Hence I knew I was missing 1 DTC, albeit a stored one...DUGHH! !!!!

First time test using Launch. There is a joke here too on the Launch, Launch sometime also goes banana hahahahah. It seems to be showing A1 doing a DTC reporting, while actually it is not.
While Xentry itself is not seeing the A1 module reporting such DTC. I do not think by MB own software, the A1 is supposed to be one of the reporting module.
This is a second "bug" I found for my Launch scanner . Xtool A30M MB software is also like this, but worse. Like 3 modules doing reporting where they are not the modules supposed to be doing the reporting.
Never mind, at least the DTC is true.


LAUNCH



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XENTRY

Below menu is called : Summary of Modules with DTC. ( I name it that ha ha ha ) It is under Sequence Filter, top right side left of the Time and Date clock.



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The Xentry bug is below : Using START QUICK SCAN , the N10/1 Front SAM STORED DTC was never broadcasted to the main page display or the Summary of Modules with DTC.




When I specifically enter into the Front SAM module, there it is the DTC, a STORED one. Dugghh !!!




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When I re-do START QUICK TEST again, now the Front SAM DTC (Stored one ) finally made it to the Summary of Modules with DTC




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Next is to see using Xentry into A1 Instrument Cluster module, is there any STORED DTC Xentry is hiding ?



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Nope, Xentry is not showing any DTC be it STORED or CURRENT at A1 module.



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What a Comedy between Launch and Xentry.
Good I have both to support each other.
At the least Xentry is still more trustworthy, after all it is from MB


Will continue later with DTC Description In Depth........ you will find it interesting

S-Prihadi

PART 2.

These DTC is bothering me.
The scenario is : I am placing myself as say a techy not familiar with MB cars and has a good scanner like Launch.

How would one react when reading this kind of scary DTC ? Why coding is even brought up ?



Of course when all DTC are read properly and slowly, two kind of DTCs will be the one to first sort out :

01. ALL of the modules with DTC mentioning lost communication with transmission.

02. The Front SAM saying a Reserve relay has a malfunction, but is is a STORED one !!! How come STORED ??
The relay was indeed REMOVED totally to simulate a dead relay with its coil burnt out, an open circuit pin 85 and pin 86. Why STORED ??? Why not ACTIVE/CURRENT DTC ?
This is the root cause of the problem, the Relay R, Front SAM knew from its internal load sensing driver that there is zero electrical load at Relay R when Ignition Key is ON.
Relay R will be energized at Ignition Key ON, not at CRANK. I can't phantom how in the world a current on-going problem but the DTC can become a STORED one ?
STORED DTC often get paid attention last,when there are many CURRENT ones. This is counter productive.

Side Note : Now I think the code name R of the Relay R make sense, since Xentry call it a RESERVE relay....LOL.




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The next DTC from N118 Fuel Computer , its description which may worry a Techy. As though as N73 EIS Electronic Ignition System is having a bad CAN BUS or CAN BUS wire/s to it.



So I assumed here the DTC of Tranny Lost-Com has changed to some other description at N73 EIS and then N73 relay it to N118 as such and here is what we have IMPLAUSIBLE DATA.
Why not N73 EIS just shut the F-K off and don't confuse N118 and us


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This Left side headlamp complaining of Gateway having issue is also not helping.




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Now let's look at the wiring of the Relay R to the Tranny computer.



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That is it, so simple. 4 wires only. 1 being from fuse 33 as power +12V.
The 3 other wires at tranny computer Y3/8 is negative ground from W15/1 and 2 of CAN BUS. Done.


I think the Dumb-Azz DTCs of choice for the scary and implausible ones is up to the software people choosing what to trigger and when. I wish do they a better job.
Me IT dummy, so I can't explain much other than the real CAN-BUS wiring involved at CAN C where tranny computer CAN BUS is connected to, the X30/21 CAN distributor.

Below is how data are being delivered and routed,re-delivered yada yada and which modules are via N93 gateway ( at Front SAM ) and that may be the cause of some description being "bad"


N3/10 the engine ECM and the N93 as the data brokers/gateway.

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So my conclusion is.... becareful of low count DTC, where its descriptions may be like a soap opera, lots of over dramatization or playing victim.... LOL.


END

S-Prihadi

I tried again removing Relay R. Engine never run between this 3rd test and all other test so far.
So there is no actual DRIVE CYCLE registered at the ECM or Front SAM.

Guess what ?
N10/1 Front SAM did not register the Relay failure at all. Launch or Xentry can not read that DTC, because the Front SAM is not keeping any.
I scan last nite and again this afternoon 12 hours later, by right the car would have slept and done its DEEP SLEEP at K2 relay in F32 Prefuse box.
Same result, no DTC found in Front SAM for Relay RESERVE failure.

As usual the Launch still shows DTC of tranny lost-com at A1 Instrument Cluster, while Xentry does show anything at A1 module.

Sometimes I wonder, how does aftermarket scanner actually identify where a DTC is coming from ?


Here is an example of Xtool A30M scanner.
Which the issues are :
01. The hood latch is always open on my car, when car at home. MB modules knows this and this is called workshop mode and no DTC will ever be produced by Front SAM module.
Xtool seems to take this as DTC. How could a scanner declare a DTC when the said module does not have that DTC ? I label M as MISTAKE.

02. The Footwell Illumination is true DTC. It is sometime that way for a LED T10 used in the footwell in lieu of the ordinary incan bulb. Front SAM when doing the brightness control sometimes realized that
the LED is not the T10 incan and will produce the DTC. When Front SAM decided the footwell is to get full brightness, the DTC will become stored, because the LED seems OK by the Front SAM.
LED is not something easy to throttle its brightness like an incan bulb.
However, those modules I ticked green : UPC , LPC, Dimming Mirror and Rain/Light sensor modules, they are NOT suppose to be broadcasting that DTC .





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This in-consistency of the Front SAM not able to sense its driver being not being electrically loaded by the missing Relay R and failing to declare a DTC CONSISTENTLY is sad.
I guess this is the reason sometimes DTC are not found fast/soon when one has problem and scan the car.


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S-Prihadi

Lo and behold.... My Xentry-C4 seems to be corrupted, a bit. I am IT stupid, I can only explain this way

I tested again using my Xentry-Passthru and indeed, A1-Instrument Cluster does have the stored DTC.

TEST METHOD
01. Remove Relay R.
02. Full Scan with baby Launch , Xentry-C4 and Xentry-Passthru. Launch still shows that A1-Instrument Cluster has the tranny DTC lost-com STORED. Xentry C4 does not. Xentry-Passthru shows A1 DTC.

03. Delete all DTCs with Xentry-C4, and supposedly all DTC gone except of course my N3/10 ECM alternator disconnected LIN, that is my own mod and it will stay forever as CURRENT DTC.
04. Full Scan using again using Xentry-C4, all good.
I deleted all DTCs on purpose using the Xentry-C4 to test my theory that if Xentry-C4 did not see the A1-Instrument Cluster DTC, it can not also do the delete DTC for A1-IC.

05. Full scan again using Launch , Xentry C4 and Xentry-Passthru, there it is the A1-Instrument Cluster DTC tranny lost com - Stored is shown when using Launch and Xentry-Pasthru but not on Xentry-C4.



My laptop with Xentry PassThru is on Bali +1 hour time zone internal clock. I have not turn on the wifi on it yet since my return from Bali. See the screen recorder time stamp on both laptops. That is Jakarta time.



baby Launch built in time zone is 2 hours slower.LOL.


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I want to re-install the Xentry-C4 software.
So I best get BenzNinja SSD instead of remote installation which wasted so much time and more prone to error I guess.

The Xentry-C4 has other issues too which pops out of the blue 2 months ago.
It can not anymore do COMPRESSION test, used to be OK and flawless.
The final CONTINUE button get greyed out and hence can't to do the test.
So I need to use my Xentry-Passthru for compression which is so slow and often crashed...LOL.

Will update when I get the SSD from BenzNinja.

S-Prihadi

Final test and I am done.

Today I tested again, this time I use all the scanners I have, except iCarsoft.

01. Xentry-Passthru and Xentry-C4 today did not show A1-Instrument Cluster DTC of Tranny Lost Com at all. Weird, yesterday Xentry-Passthru was showing A1 DTC as STORED.

02. Launch Creader shows A1- Instrument Cluster lost com to tranny as CURRENT and STORED DCT, 2 days ago was always STORED.


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Today 26th.





03. Xtool A30M also shows A1- Instrument Cluster lost com to tranny as CURRENT and STORED DCT and over reporting one more module which I do not know its exact name under MB Xentry ....LOL





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4. Autel MS906BT does not show A1 DTC of Tranny Lost Com at all.




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OBD2 section of Launch and Xtool, shows only 1 code, but cant show which module is the source. This is expected of OBD to report ONLY 1 DTC.



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I did also enter into A1 module directly with both Xentry Passthru and C4 and Autel, no DTC there.


So weird. Why aren't these scanners consistent.
It seems only Xentry C4 is consistent , now that I have Autel to compare with the rest.....LOL


CASE CLOSED.

JettaRed

iTrader: (1)

Interesting! I had the exact same thing happen today. I changed the spark plugs on my 2014 C350 (M276 NA) -- what a pain in the butt! -- and scanned for codes after putting everything back together. The hood was open and my LAUNCH Creader scanner gave me the hood latch open fault. I shut the hood, cleared the code, and it went away. I've never had that happen before.

S-Prihadi

well the more you play with it, the more of its "bug" you will find.
Latest MB software is available yesterday for me. xx.26 I believe.
Sometime with each update, the bugs can be different.

The last time I tested, like 3 MB softwares ago. On my car, Launch for low pressure fuel pump actuation does not show the pump ON symbol, while the pump is actually ON. Something like that.

CaliBenzDriver

case closed... are you sure ?
These are serious CAN-C disruptions.

It's harder to troubleshoot when each scanner calls a different set faults.
There's something weird here we can learn: how do these scanners call faults???

The LAUNCH is giving me new active faults on an the AAC Blend actuator and DCU lock motor + the previous favorites from RFK, SGW, ,....


new regulars with Launch cReader


Old RFK favorites, failed since Day-1 from factory 👎

It seems Launch provides an early warning with a lower threshold of fault %.

Now you can believe me:
CAN-C COM's are loaded with faults... Amazing solderless delivers.

S-Prihadi

Cali,
About time you software-aware person join in the party

First my biggest question is, does not a MODULE is the one producing DTC for the devices/sensors it controls ? Example the AAC.
Other modules can report say X module being offline ( Lost-Com ) because they need to hear the broadcast the X module is supposed to to when all are good and running...right ?

2nd question - Is not a scanner just a reader ( disregard programming function for now ) for data stored in a module ? Including DTCs and when the DTC or when query method is proprietary ones not
under OBD 2 standard, here is when we need to buy MB capable scanner be it aftermarket or Xentry Passthru using approved J box or Xentry official like MB dealers uses.

This will be interesting......

CaliBenzDriver

Yes Surya, you got it.

This weird thing you found is another great catch in your study.

BTW 2 thumbs up for mastering the EPC to find your parts like.

If anything the yardstick for reference is XENTRY... how does it mismatch LAUNCH scanner?

​​​​​The way I see this is like a different grading systems. Launch calls a fault based on the chassis module data it is able to accesse.

CAN-C bandwidth has its own limits. We don't have 100% of PDF needed to understand these Bosch black-boxes.

However it is very clear that partners exists across this local network: ECU <===> TCU ; ESP <===> CGW. Given enough disrupted partners, the CAN end up flooded by junk traffic. Packet Priorities are enforced... that's when the magnetic shock absorbers emphasize road bumps by late reactions. I like "S mode" harder ride until 40mph and E response on the freeway.

The funny thing about Bosch is how they design super sophisticated products with complementary savory Easter-eggs.

S-Prihadi

No idea

CaliBenzDriver

Now you understand why i say a "grain of salt"... its a digital network system that needs interpretation.
A while ago I mentioned we don't have all the tools to run a network evaluation.

However we don't ever give up! Its not because we didn't receive an invitation thats going to keep us from brainstorming a little... with our masque on.

I think scanners tead a fault count and decide what to do with it based on rules and a rating acting as a FILTER for us. These flipping boxes crunch a mind numbing amount of data. We need developer tools to brake stuff faster

S-Prihadi

Practice makes better, so we know more about the car modules respond itself to power loss and which modules reports what for other module.
As long as when trouble comes the scanner does not go banana too much...me ok ok

JettaRed

iTrader: (1)

This is great research! I just updated my LAUNCH Mercedes software to V50.26, but have yet to use it on my SL because it is in the shop for a malfunctioning passenger seat. The previous version (V50.25) would not recognize the ECM and only gave minimal info, like faults and the ability to clear them, but no information about the ECM itself. I'm interested to see if they have fixed that with this upgrade.

This brings up a point that @BenzNinja makes all the time: aftermarket scanners are troublesome and inaccurate, and that only XENTRY should be used for serious troubleshooting and diagnosis. And, as we know, XENTRY has a higher learning curve than most aftermarket scanners, but also is a serious diagnostic tool, not just a code-reader. I'm beginning to see that absent XENTRY, one should have two or more scanners for serious diagnosing. At that point, an MB Star/SDS (XENTRY) becomes not so expensive. I think my last Autel scanner was $600 or $700, easily more than a good laptop, C4 multiplexer, and BenzNinja's software.

S-Prihadi

My Autel wanted US$695.00 for 2 years update, as per its price tag on my scanner update page. I give them a big MIDDLE finger. It expired approx Sept 2023 ago.
My E400 is a 2014 and I am not interested in any update if from Autel, even if it will cover other newer cars. Anyway it will take at least 2 years after a new car appears on the market
and then aftermarket scanner could by then have reverse engineer it decently OK, I think.

Any new MB cars past 2018 I believe no aftermarket scanner can access it yet to the level we can do with our W212 due to the need to log into MB server in Germany...even for Xentry if
\without a proper account.

Me, 99% chance won't be buying anymore newer MB anyway after this E400, very unlikely.
I don't like the newer MB with so much more electronics and too small* ( non AMG ) an engine displacement with stupid 48V or mild hybrid and I can't scanner access it like I can with my oldie E400.

As for Autel expensive update :
I rather buy the Launch CRP919 BT which is blue tooth version and that will equal my Autel in BT capability, for only US$454 in Amazon during this special deal. Usually US$560

I agree, minimum for scanning but not programming, Xentry Pasthru with clone OpenPort 2.0 is a good option.
For programming we need the C4 interface like the on Benz Ninja recommended, it is stable.
I only ever get it to HANG/FREEZE once, while my Xentry Passthru with genuine Tatrix Open Port 2.0 or the clone one,both are easy to HANG/FREEZE ...I don't know exactly why,
aside from the fact it I make a command + a command change too fast ( coz it is so slow ), it will HANG/FREEZE more often hahahaha.

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JettaRed

iTrader: (1)

Yeah, I have not renewed my subscription to Autel. (I have two of the damned things and should sell one of them.) At the time, I had an SL500 with ABC and SBC, and iCarsoft just didn't cut it. I now have BenzNinja's XENTRY/SDS, Autel (2 versions), iCarsoft (MB II and V3.0), and LAUNCH Creader Elite BENZ and LAUNCH Creader Elite 2.0 BENZ, and BlueDriver. I think I have a problem and probably need an intervention.

I did have a Carly, but they wanted a subscription and disabled the device if you didn't renew. Eff them! At least other scanners let you keep working without a subscription.

JettaRed

iTrader: (1)

By the way, have you ever used all the cables that come with the Autel device? And where is the diagnostic port on Mercedes when checking the ESP or something. I always get a message about a diagnostic cable not being connected when I run a scan.

S-Prihadi

My MS906BT comes with so many cables, but I never use them. I only use the BT wireless dongle.
You mean the older Mercedes where they use the round diagnostic connector and in engine bay ?

JettaRed

iTrader: (1)

Yes, and no. I will try to take a quick picture next time I run a scan to show what I am talking about. I also have way more cables than I will ever use, but also got them with my C4 multiplexer kit. The round one comes to mind, but I don't know if it is that one for sure or where to plug it in. While I doubt it's the round one, I don't know what diagnostic connector is referred to.

JettaRed

iTrader: (1)

Ok, this is the message I wonder about.

CaliBenzDriver

> OBD Testing:
Above picture is what the Bosch ESP module displays while undergoing testing... 100% normal.

X-Mas tree is testing the related dashboard lights are working.


> Normal Driving:
While driving on the road this ESP fault is extreme bad news: Park/ Restart... $$$$

I used to get that ESP fault when under warranty. It was met by mediocre amazing lip service.... so I started to cancel Benz chaos one painted GND and one loose connector at the time.

The sad part is the experience is designed to be rocky. The networked modules operate like our pet "solenoid".


> Engineered Experience:
The above game is on the VIP bus named CAN-C:

1. Engine ECU
2. Tranny TCU
3. Gear Shifter ISM
4. Wheel brakes ESP
5. Fuel tank pump LPFP
6. Front Signal Actuation Module F-SAM.

It's built to underperform quietly until it screams. How do I know? I have had it bad before I made it good. So I know why what and where.

Nice and quiet, fault-free:

• the banging tranny
• the wandering car
• the kicking rear end
• the battery drainage
• the Yo-Yo discharge
• the engine rattle...

When everything we can check is amazing, we can extrapolate the condition to what we can't check. Practically I'll rework the ESP module this year.
ECU + TCU are built to normal honest working standards to prevent bugs from blowing up mechanical assemblies into pieces. Good then!

These cars are great once given a chance to work normally. The network modules are setup to perform much like the oil solenoid.



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BenzNinja

iTrader: (4)

no need for account as BenzNinja member
I do 99% of all online jobs for free (no keys)

JettaRed

iTrader: (1)

The dashboard lights were on because the car was ON with the engine OFF.

I never noticed if the ESP related display happens with XENTRY scans also. I'll have to watch for it next time I scan with the XENTRY.

S-Prihadi

Yours is special case Peter

S-Prihadi

Its like that : the Christmas Tree when doing full scan. Even sound system will play a while, parking sensors will beep if you have objects close enough to those 8 sensors and the LED headlight will play around with its aiming too.