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· Registered
1999 S500; W140.051; 2003 E320; W211.065; 1973 220; W115.010
1,204 Posts
Discussion Starter · #1 ·
Car: 2003 W211 E320 sedan with 'Avante Garde' option.

MOST ring was open due to retrofit of android headunit installed with wired architecture that completely bypassed the MOST system. There was 'open ring' condition after this install as I didn't have enough MOST 'loopbacks' to try to close the loop. This is a car that I got for my daughter and I was 'out of time' for repairs so I had to leave the 'open MOST ring' condition for later.

Some months later my daughter came to visit and I was able to get back into furthering my research project on the MOST system.

I wanted to get rid of MOST & AGW completely as it wasn't doing anything useful anymore.

I was able to get SOS system completely disconnected to get rid of the annoying periodic "SOS" errors.

I was able to re-code thru Star to remove all options in MOST ring. Unfortunately there are not coding options for AGW & Command unit. I set all options in MOST as [Vacant]. Then I put a MOST loopback at the POF connections on the AGW. In effect, this made a 'closed' MOST ring with the AGW as the only device.

Surprisingly, this will scan free of errors for the AGW system, but there are still some errors under System Diagnosis but this does not cause any MIL errors in instrument cluster.

I still had and "SRS" MIL I thought was due to the passenger seat weight sensor mat, but scans seem to indicate that it may have something to do with disconnecting the SOS unit.

There is a Telecommunnications Module (N112) mounted in the trunk that is next to the SOS related box.

N112 module is not on the MOST ring, but I think that the chassis number is causing the system to generate an error because SOS is not present. I think that the Telematics system does some check and generates the "SRS" malfunction because it doesn't find the SOS connected on the MOST ring or via the electrical connector which is also unplugged to the SOS unit.

Error details:

Control unit: AB - Airbag - F (Fail)-

MB number: 002-820-6426 HW version: 47.2001 SW version: 24.2002 Diagnosis version: 9/0 Pin: 101

Error Code: 9030

Text: "The coding for the digital crash output to control module N112 (Telecommunications control module) is faulty".

Status: Current and stored

Any ideas on the nature/reason for the error cited above or how to code the car to resolve the issue with N112 without "SOS".

· Registered
1999 S500; W140.051; 2003 E320; W211.065; 1973 220; W115.010
1,204 Posts
Discussion Starter · #3 ·
I did actually get that problem fixed about 7 months ago.

In Star, if you go even one 'F3' step past the explicit warnings in 'Special Settings/Initial Setup' for AB Controller N112, you will unlock the controller and can ONLY lock it by answering all the questions about installed equipment. This is the small door with warning signs that nobody should really go past.

Even worse, as you enter the controller entries, Star displayed weird entries that didn't match the previous configuration; e.g 'Country of Sale' was shown as 'Germany'; uh oh ... abort ... too late...

I have yet to find a person who has actually unlocked & relocked the AB Controller.

I was worried that I would be asked for answers that I could not provide without a VMI report, but I was desperate enough to have to give it a go without it.

I made a complete MOST ring without the Command headunit that I had replaced with an Android unit and wired in analog to the speakers, bypassing the AGW. I coded MOST ring to match 'actual config'.

I went back into Initial Setup in the AB controller. It showed the Unlocked status and didn't display the same dire warnings; we were past that stage. Instead it displayed reassuring notes to say that the each step would be 'guided' and that the entire process 'must be completed to lock the controller'.

Again, first entry field 'Country of Sale' was shown as 'Germany'; I entered USA, Surprisingly, most other fields either displayed a value that was consistent with the vehicle or were easy to answer items. The process went thru the AB controller then something mysteriously named ARMADA. I finished the whole process only to be told that the 'Initial setup could not be completed because the vehicle configuration did not match the entries to the controller'. The controller(s) remained Unlocked.

I concluded from this that the system was polling the actual configuration and the fact that it did not match the coded entries would not allow a successful completion of the Initial Setup.

The problem was not with my entries into the AB & ARMADA controllers, but the coded entries in the modules.

I had to go back into AB system and add back in entries for Emergency Ctel; SOS & even had to configure 4 side airbags from 'no entry' to 'Active'. How those 4 side airbag entries got recoded to 'no-entry' is another mystery. Essentially, the coded config HAD to match the installed equipment as the CGW can poll the system and 'knows' what is connected. ONLY when all all that connected hardware matched the coded config could the 'Initial Setup' of AB & ARMADA controllers be completed and the controller(s) be 'Locked'. A 2nd pass thru the 'Initial Setup' of the AB controller was successful and the controller was Locked.

The SRS light was now off.

Now I see why nobody messes with Initial Setup of AB & ARMADA controller N112. It's firstly because of the dire warnings of the "safety-critical" hardware AND secondly due to the fact that you can't really change ANYTHING as the system won't let you make any config that doesn't match the polled hardware and the VIN. You cannot replace N112 with a used part. Once that VIN is put in there, it's not going to work on another car. It can only be replaced with a new unit and you can transfer coding with SDS. You still have to get authorization for a new ESN number from cell provider as part of the replacement process.

What a difficult, complex and troublesome architecture.

Once again the W211 is an 'eye-opener' compared to my simpler W140.
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