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Discussion Starter #1
If “BMW Computer Systems for Dummies” exists, I have NOT found it, so hence my perceived need for this Thread. This Post is LOOONG, and should ONLY be read by those willing to think, examine their concepts about the subject matter, and/or take the time to offer their own concepts, along with facts to support/ explain those concepts.

The problem ALL of us have trying to understand electronics: CONCEPTS. You do NOT need to understand the complexities of how chips work, how they are programmed, programming language, or any of the really detailed and tedious stuff IF you have a decent WORKING MODEL or concept of how the computer system in your car works, and its capabilities in interacting with a Scan Tool or Diagnostic Software to provide diagnostic assistance.

A CONCEPT is nothing but a simplified summary or "Model" of how you think something works, and as you learn/ experience more, that Concept should be re-evaluated & updated, modified or replaced. Concepts should be treated like feelings: they are neither Right nor Wrong – they just ARE. If we are reluctant to examine and discuss our concepts, for fear of being told they are WRONG (they may NOT be an accurate “model” to explain facts, but they are STILL our actual concepts at the moment), we will never make an effort to analyze and improve those concepts.

So in an effort to improve my own Concepts, and get anyone taking the time to read this to think about your concepts, I will describe my own NON-EXPERT concepts of my BMW's computer system, how INPA diagnostic software works, and invite others to share their concepts to improve mine (and others’):

1) The E9x BMW models have ~ 20 different "Computers" or control modules (give or take a few depending upon options/equipment).

2) Those computers are "Networked" via BUS communication wires (as opposed to Cat5 or Wi-fi on home/office computer network).

3) As a rough analogy, you can think of the OBD II socket as the "Router" into which you can connect the Scan Tool Cable (or wi-fi adapter if wireless connection).

4) Once you have connected your Scan Tool or Laptop Cable to the OBD II socket physically, you then have to establish electronic communication with the "Router" by selecting the correct "Communication Protocol" (Computer Language) that will be used in this communication. Most Scan Tools have a setting you can select to automatically detect & select the correct "Language" or "Protocol" so you don't have to know which one to manually select.

5) Once the "Connection" to the "Router" or "Network Hub" has been established, you will see some screen that confirms that connection. If connection was NOT successful, you should see some indication of why the Connection failed.

6) Certain "Functional Jobs" that relate to ALL "Computers" or Control Modules can be run on the network when you FIRST connect, if your Scan Tool has capability to do that. For instance using INPA software on a laptop, when you first connect you can select "Functional Jobs" and see what is basically a database "Report" on any Fault Code saved in any of the ~ 20 modules (ALL modules report). This is a good "First Step" in determining what Fault Codes have been saved in any module, but it's basically just an identification of any module with a Fault Code saved, and you need to "Connect" to each such "Computer"/ Module with a Code saved to do any real diagnostics, as explained below.

7) Once connected to the "Router" or "Network Hub," you can then Select a particular "Computer" or "Control Module" (such as the DME-Engine, or EGS-Transmission) to which you wish to connect. This is analogous to a “Peer-to-Peer” computer network where you have certain privileges to view information on certain computers' hard drives, in certain folders, or to perform certain “remote” operations (Activations). AFTER connecting to a particular module, you can then do some/ any of following basic functions related to THAT PARTICULAR Module:

(A) View Module Information: Info about that module, such as its BMW part#, supplier, SGBS (ID Code), Software or Hardware Version, etc. You are simply reading text information saved in Module Memory, as you would read a text file saved on computer Hard Drive.

(B) View Fault Code Information: saved in Module Memory, or saved text on HD. The information that is saved in the Module depends on the particular module. In the case of most DME Fault Codes, you will find:
(i) Fault Code number: BOTH BMW Fault Code AND corresponding P-code are there if your scan tool can read it them;
(ii) Definition of Fault Code: a short description of the fault, such as "circuit low," "implausible signal," etc;
(iii) Fault Details and/or Freeze Frame Data: mileage/km at which Fault Code was saved in memory, engine or other conditions existing at moment code was saved (such as temp, load, RPM); other information (depending upon module) which may include number of times fault occurred, whether fault is currently present, whether the fault would illuminate a warning or SES light, and more.

(C) CLEAR Fault Code(s): which is usually a good test to see if the fault is just a momentary "hiccup" that won't recur again, or if it is something that won't go away (for long ;-). I always save a ScreenPrint of any Faults & Freeze Frame Data or Fault Details, BEFORE clearing a code, so I have a good record or history of Faults in that Module or System. Obviously you should clear the code(s) AFTER recording that information if you believe you have fixed the issue, OR you want to test for recurrence. It should be noted that one of the greatest benefits of using laptop-based software for diagnostics is its ability to SAVE the Fault & Freeze Frame Data in a proper Folder for historical reference. You will NOT have an accurate recollection of ALL the details 6 months later (perhaps NOT 6 hours later ;-)

(D) Parameter Reading, Status, or Live Data Readout: Each of these terms means the same thing to me: "seeing" or reading certain "Values" such as Temperature, Voltage, RPM, % of max RPM or position, etc. These are usually "Computed Values" where the DME or other module to which you are connected shows you a value based upon the voltage of a signal it receives from a sensor, or a speed/ RPM computation based upon a square wave signal.

My concept of these "Status" screens is that I am reading values computed by the DME/ Module based upon "Inputs" it receives from sensors, feedback potentiometers (A/C flaps ;-) or even from other module(s) to which it is "Networked." Some INPA screens give you RAW Voltage readout for sensors, which by itself, without knowing what the value should be for certain situations, is NOT terribly helpful to the average person (Geeks' Delight ;-)

That Live Data Readout may be something as simple as whether the contacts of a certain switch are open/OFF, or closed/ON, such as for light switches, handbrake switch, fluid level switch, etc.

(E) Activations/Steuern: YOU are providing "over-riding input" to the Module that causes components, such as Motors, connected to that component to operate at a certain speed or position, or NOT operate at all, for test purposes. Your car's computer system has the built-in capability for external control or "Activation" of the various motors, including fuel pump, coolant pump, windows, radiator fan, etc. If your diagnostic software (such as INPA) or scan tool has the ability to provide the proper input to the module to over-ride control, you can test components that way. Don't forget to "Return Control" of the component to the DME or other controlling module when testing is done. ALSO, make sure "Test Conditions" such as engine on/off, voltage, temperature, or other prescribed test conditions are complied with. These appear at top of INPA "Steuern/ Activation" screen. Don't know about various scan tools. Some Modules do NOT allow Activations. For obvious reasons, Air Bag Activations are NOT offered. :tsk:

Sorry for the length of this post, but I haven't seen anything ANYWHERE online that actually discusses (1) the CONCEPTS that Diagnostic Software users have developed, or (2) that Summarizes Capabilities of the Software, such as INPA. I emphasize AGAIN that I am NOT an expert in this area, have only been “messing with INPA” for about a year, and am basically honestly putting my own concepts out there for others to “critique” and suggest other ways of looking at the same thing (other/ better analogies). If we take too much “pride of authorship” in our concepts, we will NEVER improve them. One of the advantages of Artificial Intelligence is that ego is NOT included in the programming (AFAIK). :)

I would hope that others on this Forum would take the time to think about those two subjects and share their Concepts & knowledge. An overview or Function Summary of Coding or Programming, and the use of BMW Standard Tools for such purposes would ALSO be helpful if anyone feels inclined to offer such, or a cite/ link to a good existing reference.

George
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 99K miles NOKIAN WR G3 12K miles
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BMW Advanced Vehicle Diagnosis. 224 pages PDF

My impression is that many presume knowledge that is not valid.

I just noticed that my file is 9.7 MB while this meeknet file is only 7.15 MB

All Intellectual Property is copyright, and BMW has not released any files, that I know, to the public domain. Public access is not a release under DMCA.
 

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Kostspieliger Spaß Quandt
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Your link was to a private google drive - No need for the link to be password protected - BMW training materials are widely available:

BMW Advanced Vehicle Diagnosis - public link

I realize George is talking about using INPA here but there are other programs that perform similar functions. The Snap-On software for diagnosing/servicing BMW's is very good and they have a thorough explanation of how to connect and the various modules purposes.

BMW Vehicle Communication Software Manual

If you are using P.A. Soft BMW scanner - there are two essential sources -
PA Soft for Dummies
BMW Scanner 1.4
 

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Discussion Starter #4
I realize George is talking about using INPA here but there are other programs that perform similar functions. The Snap-On software for diagnosing/servicing BMW's is very good and they have a thorough explanation of how to connect and the various modules purposes.
Thanks to Doug & Ian for the references to explanations of how various proprietary diagnostic software works. Yes, my posts are usually too LOOONG, but NOT 224 pages (thanks Doug ;-)

The reason my post above was 3 pages long is that I was trying to describe the "concept of a CONCEPT." Encarta (yes I still have than on my laptop hard drive 'cuz its Thesaurus includes many synonyms) lists the following synonyms for "concept": "idea, notion, thought, perception, impression, conception, theory, model, hypothesis, view, belief".

As I was using the term CONCEPT, I was thinking of a "Model", the definition of which (Encarta) is: "A simplified version of something complex used...to analyze & solve problems."

So what I am requesting in this thread from other Forum Members is NOT recitation of the mind-boggling details & complexities of the E9x "Computer System" or "Control Module Network." Rather, I asking about YOUR "Model" or simplified version or "Concept" that helps YOU understand how that "Control Module Network" works and what it is capable of in analyzing component function, and solving "Fault" issues.

First problem is that for many people, their "CONCEPT" of diagnostic software is: "something you use to tell you what part to replace." :rofl:

If we can't get past that: Oh well, Happy New Year!!

BTW, I was really trying to concentrate on the capability of the E9x "Control Module Network" to provide certain diagnostic information to the user of ANY Scan Tool or diagnostic software installed on a laptop, regardless of the brand used. Whether INPA, ISTA, Snap-On, Carly, Foxwell, Creator, BT, or whatever. In fact it was Alex's post related to his use of a Creator C310+ that caused me to do this thread.

I am aware that each Scan Tool and Software has its own capabilities or limitations, so what I was trying to focus on was what the E9x SYSTEM Capabilities are, and let each person try to figure out what his particular Scan Tool CAN/Cannot do as far as utilization of SYSTEM capabilities. Since INPA is the most advanced software I have personally used, I was merely using what I've seen it do as evidence of what the E9x System is capable of.

Thanks again,
George
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 99K miles NOKIAN WR G3 12K miles
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So TL;DR is good enough for George? We have so little time and there is so much to read that trust and verify leads to respect. Yes, BMW technical literature is poorly translated and written to a particular background, but the information supporting the concepts is there, and the concepts are common across the product line.

Complexity is tough to wrap your head around. Some can and some can***8217;t. TTFN
 

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Discussion Starter #7 (Edited)
George, try ISTA. It loads a visual flowchart of each module and colour codes the module if a fault is found. It is much more intuitive than INPA and provides a friendly GUI. It is designed for the Serivice Tech to develop a Test Plan of action to resolve issues.
Thanks Ian, I intend to install & use ISTA in the next year. My "Concept" of ISTA from what others have said about it was that it was more of a flow chart type approach where one simply follows the trail of bread crumbs until the goal is reached (perhaps actually acquiring some knowledge along the way if NOT in too much of a hurry ;-). My training and experience to date has been a more "engineering-oriented" approach of attempting to understand how the components of a system work, what diagnostic/ test aids are available and how they work, and then using that information to solve the problem relying on my concepts of those things.

Perhaps that concept has gone the way of the dinosaur and "nobody does that anymore," but I get the impression from what you have posted in the past that you have tried (successfully) to do what I describe, and have highly recommended INPA for those who approach diagnostic problem-solving in that way.

Please correct my impression if NOT accurate. :)

Happy New Year!
George
 

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Ista integrates that tis site into it . (which is a great site)
I think its safer . Inpa gives you ultimate control
but you can do damage with it if are the type that
pushes buttons to see what they do.
Also if you nicht verstanden Deutsche it's all in English.
The guided troubleshooting procedures would tell you how
and where to set up your instruments. Scopes and whatever
and what to expect . Might be in tis I don't know.
 

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Kostspieliger Spaß Quandt
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Think of ISTA like INPA for (English Speaking) Dummies ( actually ISTA is available in around 9 languages if you download the correct dB file) If you're comfortable and adept with INPA ( as you have shown) you might feel cheated by the poor depth of analysis offered by ISTA? What I have found along the way tho is that no one tool is superior for all purposes. Some are better in certain areas. I've only used ISTA a couple of times on vehicles produced prior to 2007. I rarely use anything else on newer bimmers. INPA is great for certain older routines and monitoring live data - not always capable on newer BMW tools. Hell I've even got laptops staged with different versions of INPA - each with different specialized diagnosis and adaptation routines for different chassis and module sw versions. Other apps have proven good too for limited functions - Carly comes to mind as a good portable PID logger - especially for BMW vehicle specific data. PA Soft is great for fast safe module coding up to around mid 2007 and some other not so well known and contentious functions like odo correction and *** reset. NCS Expert is the king of kings for coding older bimmers but is limited in safety and support. No BMW tool beats OBD Fusion for in depth emissions related engine diagnosis on any model year since @1995. Snap-on Solus is the quickest and most reliable for major module error retrieval across any year > 1996 (DME, EGS, ASC/DSC etc) but limited in depth. Carsoft for BMW - haven't used it now in 15 years. Good for 80s DME's though, so I keep it.

I tend to a wide array of bimmers from the 1980's to 2013. It's often different tools depending on the car and task. If I had to give everything up but one tho - INPA would be the one I kept. I think most folks only need become versed with the tool(s) that they need for the vehicle(s) they are supporting. It does help though in the learning process if the tool is simple to use (like ISTA). I've seen too many new users to NCS Expert and similar tools brick their older modules by trial and error.

I have an inquisitive mind and I don't always believe what I read, especially on this medium. My nature is to take things apart to see how they work (or fail) for myself. Remember too the target user for BMW produced factory service tools has a narrow scope, ( to quickly and as best as feasible, accurately diagnose the customers concern) - much less abstract than the perspectives on here.
 

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Discussion Starter #10
...I don't always believe what I read, especially on this medium. My nature is to...
WHATEVER do you mean?!?! You ACTUALLY read critically and analytically -- shocking Concept, ABSOLUTELY SHOCKING!! :rofl:

Thanks again for sharing your knowledge & experience,
George
 
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