We Decided How to Read Trouble Codes for a 1998 Mercedes Benz 500sl

Mercedes older serial diagnostic fault code reading. W124.R129 1980's – 1990's era

As y'all are reading this you will probably exist wishing to extract a fault code or articulate a error indicator lamp from the dashboard of your older Mercedes Benz model vehicle. You will have likewise likely been frustrated by reading a multitude of confusing data, following expressionless web-links and generally reading several dissimilar takes on the same subject – mostly from well-meaning members on forums or online motor clubs who unintentionally 'dingy' obtaining the most correct and technically accurate data.

Well the culling information source you take been looking for is here, hopefully articulate and accurate enough for your needs. I have collected the following information together in one identify to save the frustration of trying to locate and observe most that y'all would e'er demand to tackle this job.  I will not repeat what has already been expertly written on this subject, you lot tin find links below to these sources to expand on what I have noted here.  What I have done is written about the important parts and included some vital pieces of information that you may demand to refer to – you may find this data at the other linked sources besides, but at least information technology will remain available in some other Mercedes resource should any of it disappear from the web, as a dandy deal on this subject already has.  Enjoy!

Carsoft Interface connected to R129

MB Diagnostic History

Back in the day when Mercedes starting time ventured into the world of on board diagnostics in the era of the 1984's W124 and its stable mates they began to introduce electronic lawmaking diagnostics. The offset existence either through an 8 pin (X92) or 16 pin (X11/four) foursquare cake fastened to the bulkhead. At that place were actually only14 diagnostic pins on some 16 pin X11/four models as slot ii was a small momentary button and slot four was a small red LED used to read out fault codes flashes. All was needed was a paperclip or brusque banana plug jumper to ground the required pins and but watch the number of flashes. Codes are resolved from comparison of flashes to fault codes on a written list.

Counting flashes activated past grounding individual pins continued through the square block connectors to the 38 pin round X11/xiv diagnostic socket to most 1994. This was commonly located within the ECU box and was accesses past removing a sealed access cap. Although 38 pins were used only the pins relating to build options were loaded and equally such gave diagnostic flash / blink access to the cars individual modules.

USA and some EU versions around 1994 were equipped with both a 38 pin X11/14 and the now common 16 pin oblong OBD port nosotros employ today. The reason behind this was that MB at the time had to comply with export requirements that necessitated access to emission data through OBD standard protocols. At this fourth dimension Mercedes added the OBD port under the nuance, in some cases near the steering column but to give access to emission related diagnostic codes, all the other electronic systems were dealt with through the 38 pin socket as before. So very much a hybrid situation was in existence – seemingly done equally a quick set up to continue to sell cars in the US.

Mercedes were in parallel developing their own digital diagnostic system and not following the industry standard of OBD1/2. From August 1995 production date Mercedes phased out the analogue blazon of flash/blink diagnostics in favour of their propriety digital code reading organisation. Without going into also much particular this new organization used ISO9141 communication protocol to access the vehicle electronics via a common communications module. This used both a Yard-line and L-line connection and Mercedes own communications language to admission the organisation. Even though the communications standard of ISO9141 is the same as used on OBD2 systems the way in which information technology talked to the modules was bespoke – and this is why you cannot utilise traditional OBD2 readers on systems of this blazon. Fortunately Mercedes saw the error of their ways and only ran with this for about a six year window opting to take on the OBD2 standard across the board from 1999 (Thank goodness!)

Types

Then given the in a higher place history there are three primary diagnostic code reading methods (actually four) that you lot may come across in the model year window of 1984-1999 (Please note all dates stated are approximate and for guidance but) What is a little confusing is that Mercedes in their wisdom used the 38 pivot diagnostic connector for both the analogue and digital systems making it very hard to visually identify what arrangement you are dealing with – they even used the same pin number allocations to reflect the connectedness to individual system components !

The diagnostic systems that were available during this catamenia are:

…………………………………………………………………………………………………………………..

Flash / Glimmer – circa 1984 – 1994
Flash / Blink with OBD X11/22 Under-nuance for United states Markets circa 1993 – 1997
                        (OBD Port for engine management only)
Mercedes Proprietary Digital Diagnostics 1995 – 1998
OBD2 Standard 1999 – on

…………………………………………………………………………………………………………………..

Useful links that have smashing information and should be used for reference.

http://www.mbcluster.com/Media_Diagnostics.htm
http://www.202tech.com/howto/leddiag.html
http://www.onboarddiagnostics.com/page03.htm
http://k6jrf.com/mb_scnrs.html

Here is some important information that budding MB SL R129 / W124 diagnosticians volition need.

To build and use a unproblematic Mercedes Flash / Blink decoder,  here is the excursion diagram.

Here is the link to the Cs1000 Baum Tools Manual code reader that contains about of the detailed information you may always need regarding, connections, pin outs etc specifically for Mercedes Benz models. Importantly it contains the analogue wink / blink error code fault decoder information.

To read codes:

1.Connect the code reader cables to pivot 1 for the blackness or ground connection and pin 3 for the 12v supply on the 38   pin diagnostic socket.  Select your chosen test bespeak (module connection) to test from the following 38 pin socket diagram and connection pin-out tabular array.
2.Turn ignition on, engine not running.
three.Press momentary switch for two-four seconds, look and so count flashes.  Notation down the number of flashes on a piece of newspaper. Repeat the process until the first flashed code repeats.
Note:A unmarried flash means  – no error stored

To clear codes:

ane.After reading a code, press the momentary switch for 6-viii seconds so release.
2.repeat this for all stored codes.

Mercedes SL R129 38pin Diagnostic connector pin out diagram and function listing.

Please annotation not all pins are loaded in every model, the quantity of available pins depends on model, version and fitted equipment.

Later MB Proprietary Digital Diagnostic Communications – 1996 MY (R129)  SL

I take discovered that this menses model (The one I take!) was fitted with a combination of both counterpart (Blink / Flash) and Digital Mercedes Proprietary diagnostic systems.  I do not accept an OVP module (voltage controller) I take a Base Module.  The base module can exist accessed with the blink/wink code reader, faults read and cleared on pivot viii, while other organization components tin can be accessed with the Mercedes Proprietary reader from the same socket!

Yet that is about the extent of any function attainable by this method.  As stated earlier higher up to read engine codes or ABS codes etc the unit has to be connected to a capable electronic code reader.  The Autel OBD2 reader I apply for most of my modern day Mercedes diagnostics does not work – even with the OBD 16 pin to 38 pin adapter.  This is because the protocol or access language is specific to Mercedes.

About the only system capable of reading and accessing the majority of codes through the Mercedes proprietary organisation is the Carsoft V12 organization.  This is a Mercedes single model diagnostic tool made in Kingdom of belgium.  Its kit consists of a 7.two interface module, selection of leads (for all MB models) Operating USB security dongle and Carsoft V12 PC software.

I will comprehend the use of this diagnostic equipment in some other mail shortly.

For those fortunate to own post 1999 vehicles of the R129 stable your car should exist equipped with a fully compliant OBD2 diagnostic system, 16 pin standard diagnostic port and the capability to exist interrogated by most any off the shelf OBD2 reader. (Lucky you!)

Air conditioning organization – self diagnosis (R129)

The AC control unit in the R129 Mercedes SL model along with a few other MB models of the time (outlined in the CS1000 transmission) could be accessed to diagnose system problems by retrieving error codes straight from the Air conditioning command unit of measurement console in the car.  Instead of counting flashes, the Ac console displayed fault codes on the two digit LCD temperature display and were cleared past a combination of pushing buttons.  Data for the reading and clearing of the diagnostic codes of the AC unit for the R129 can be found on page 90 of the Cs1000 Baum Tools Manual.  Information on other period MB models that had like AC control consoles is included in the to a higher place publication.

We Decided How to Read Trouble Codes for a 1998 Mercedes Benz 500sl

Source: http://www.mercedes.gen.in/mercedes-older-series-diagnostic-fault-code-reading-w124-r129-others/

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