I'm the recent owner of a Mercedes S500 and have had to start doing work on it.

I bought myself a cheap $40 diagnostic tool (16pin) unit to read and clear fault codes. The problem is, it only accesses the basic modules of the car. The S class is so complicated with several modules and systems, I think that I need to buy something a little more powerful. My EC (AC off) light has now come on and I can't clear it with my crappy diagnostic tool because it won't access the AAC)KLA (climate contol) system.

I did some research and the best value for money tool that seems to do almost everything is the Launch X-312 tool.

I hesitate because it's neary $2,700.

Its going to cost me $120 to get the MB dealer to clear the AC DTC (Diagnostic Trouble code) . This means that I would need to clear 23 codes before breaking even. The tool is more for mechanical workshops and works on many cars. I only need a tool for myself.

Does anyone have any advice on what diagnostic tools they use to work on their Merc??

 

Error,

It's Launch X-431 tool. not x-312 as posted above..

 

Hi Aazapf,

I'm in the same situation. I've taken my car to the dealer, and they always do a wonderful job, but I do not like the car having secrets that I can't see! It puts me at a disadvantage, so I guess its a "control" issue with me. My wife has noticed that alot of people with Mercedes, work on their own. My only explanation is that they must like the cars so much that they really dont want anyone else messing with it.

I too have been shopping for a diagnostic tool, but not being in the repair business I don't want to over-spend. I've seen them from $45 to $3000. The one I'm considering now is the Ampro OBD2, I forget the model#, but it is supposed to display the alarm codes with a definition/explanation, show realtime sensor readings while the car is running, and allow resetting of codes etc. It comes with a book to give you some general trouble shooting ideas etc. It cost about $300 at pepboys, which is a store which I typically would NOT buy parts from, but rather oil, wax, towels, etc. The store manager told me that all OBD2 systems, codes, plug-ins, were basically the same, and the package stated that it worked on all.

I haven't bought it because I'm not confident, regardless of claims, that it will work on my car. If you have had a Mercedes long enough, you realize that a lot of things are exclusive such as tools, threads, sizes, etc. So I do not want want to make the mistake of buying this thing and find out that it cant do all its functions on a Mercedes. I think I'll ask the manager to demonstrate the device on my car, and if it works, I'll buy it. I'm sure it won't read everything the "mothership" can read, but if it can keep me from having to drop my car off to find stupid things like air leaks etc, I'll be happy.

C

 

I think you're right. They don't want to encourage the DIY guy to mess with the car. I think it's a money generating venture.

http://www.x431usa.com/Roundel%20Cra...de-May2006.pdf

This website pdf had a table at the end that compared various units and stated which systems the diagnostic tool would penetrate. There was only one that would access all systems and do all the testing. Unfortunately is around $5000!

My other concern is the change in standards. Currently OBD II is the norm but OBD III is going to be released. Also the CAN protocol seems to be the industry standard. I'm not sure what my 2001 Mercedes has. Given that I'll probably keep the car of at least 3 years, I think that I'll need to reset the codes on various systems several times over.

$300 for the unit you're talking about sounds great if it accesses ALL systems. They're are just so many.

Check the table out in the end of the article above.

Cheers
A.

 

Hi,
I don't believe this tool will access modules other than the engine/trans.
I use a DynoScan (Auterra) which is great since the software runs on a Palm PDA. Auterra advise me that they are currently working on an upgrade to access all modules on the CAN.
I'll be interested in where you end up.
Stuart.

 

Hi,

Does your Dynoscan unit access all modules?

How much do they cost?


Running on a PDA would be good.

 

clearing the EC light is not as easy as clearing the faults on other control units.

even by using star diagnosis, you have to go through different menu (control units, body, airconditioning...) to clear it.

just let the dealer do it.

 

thanks for the heads up. I will let the dealer do it this time.

I'm also glad to see you didn't retire at 6000 posts...


I still think a good diagnostic tool may be a good investment.

I can always use it on other cars later down the path. With electronics and computers becoming so integrated into cars, I feel that anyone wanting to work on their cars themselves is going to need one..

My trusty mult-meter just doesn't do it anymore.

 

BMWs were a nightmare ten years ago; Today, 125 processors? What the hell for? ( flop, there went that sale)

You know I'm just not into this. I think computers can be fun etc., but they are ruining the concept of a personal vehicle. If they are going to put all that crap in a car, they needn't expect me to pay for it. I'm not against clean air or effeciency, but this holding the customer hostage over a friggin computer code is crap. Then there is the crime, the rumors of onboard viruses, spying, recording your travels, calls, preferences, automated traffic citiations, killing your car by remote when they need business, etc. But what's in it for me? If I wanted someone else has complete control over me, I would take the bus or train. I'm not going to pay somebody $700 to flip a switch so I can drive my car. Very fragile ground, this is.

Mercedes has a good dealer here, and they have been fair with me, so I keep buying their cars. But there is NO WAY I would EVER buy another BMW. There's nothing like a $5300 repair at 20K miles to kill all possible future sales.

GRRRRROOOOOOOWL!

B

 

DynoScan cannot at PRESENT access all modules but they are working on it.

Can't remember exactly how much but it was only about 220 USD. You have to provide your own Palm. Extremely robust. You get live data streams and can graph, export to PC etc.