Understanding error codes
 

Hello,
First I would like to know where I can buy the necessary software that can understand error codes. Second, what type of machine or computer is needed to "hook up my car" do diagnose problems and codes.
Thanks,

Hi,

For which car?

For the 300E, you need a multimeter with a duty cycle function.

Sears sells one for about $30.

Not sure about the other car. I believe that was OBD1. I have seen a few scanners on ebay. You might want to search on Mercedes tool.

Regards,

I need it for both cars. What are they called at Sears? What about software to understand the codes?
Thanks!!

Allan:

Larry mentioned the model he bought from Sears in this thread:

http://www.peachparts.com/shopforum/tech-help/50818-can-someone-recommend-good-basic-voltmeter.html?highlight=multimeter

The 300 is easy, the e320 not quite.

The problem with the e320 is that many systems have onboard diagnostics and the information isn't sold by model and year its sold more by system. All of the data, theory, and diagnostic procedures do not exist in one location (unless it be my office [bg]). Proper diagnostics would require at least two forms of manual: the ETM (electrical troubleshooting manual) and the DM (diagnostic manual). The ETM can be bought with the 124 CD. The DM is a professional grade manual and if still available in print would cost over a grand I would guess. The DM is purchasable by the system; such as A/C. I have 16 volumes, about five feet long on a shelf. These only go to 98 as after that its on the MB info system WIS.

The tool necessary depends on the level of access needed. Full access would require a SDS which runs somewhere over $21k. The best aftermarket tool I think is the Baum tool www.baumtools.com , which I see is available right now for 2000 plus modules. A very good tool for a little less money would be the AST tool www.asttool.com .

The car is too old for the cheap PDA OBDII tools. They only do the engine side of powertrain anyway.

Your car can be accessed by the impulse method for most systems for fault codes. To try and repair a car from fault codes alone would be similar to interpreting a novel from reading the table of contents. Ninety percent of diagnostics is done with actual values, activations, and adaptations, only available in the higher scanners.

error codes
 

hello everyone

i was going to ask on a new thread then i found this one.

my question is similar. i would like to be able to read error codes and then know what they mean and what to do.

i have a full range of multimeters. analog digital etc: but i am curious about the sears unit so i will pick one up.

so i will have the correct vom for the task. are there other code readers etc; that i need to get. currently my 2 vehicles are the 87/88 420sel. i haven't looked but i don't think the 72 uses a code reader....but if it does i'd like to get that as well.

thanks again for everyone's input.
craig

There is nothing special about the Sears unit except the price for a unit that has frequency and duty-cycle. Most modern multimeters have these functions.

i'm surprised to see my digital unit (amprobe) does not have either duty cycle or freq. i have 3 units here at work 2 man and this one. i'll check the one i keep at home before getting the sears unit

any info on the code readers etc is greatly appreciated.

tks much
craig

You might read my article in the DIY section: Evaluating engine controls.

It shows the use of some standard electronic equipment testing systems similar to yours.

Hi,

Steve's FYI section combined with the CD manual helped me determine an 02 sensor problem.

Getting to know how the MB fuel delivery system works -- at least in basic terms -- is needed. Takes some study and connecting the dots.

Steve's article goes a long way to making the process easier.

Bottom line: If you don't have a CD manual, get one.

Regards,

Question....can I.....
 

....reset the code after changing the fuel filter? I searched yesterday on "check engine" light and came up with either a filter or an O2 sensor being bad. The typical symptoms (from the thread) are not happening, poor economy, "rich" exhaust odor, poor idle, so I figure the filter. I read and printed Steve Brotherton's piece in DIY and have an idea of what to do to reset, multimeter is in top tray of my toolbox.

Thanks in advance and many thanks to all who help each other out in this forum.:cool: