Mercedes-Benz Forum banner

Worth buying diagnostic equipment?

931 views 8 replies 6 participants last post by  deanyel 
#1 ·
I'm wondering if it's cost effective to purchase diagnostic equipment rather than paying a Mercedes mechanic to run it everytime.
I recently purchased my first Mercedes, a 1994 S500 (W140). A friend told me that it's not worth purchasing the equipment because you still need someone to interpret the codes. Isn't there a guide that that lists what the error codes mean? I guess I still don't understand why I can't do this myself. What am I missing???
 
#2 ·
You can get a basic code reader, but it won't be able to read half the codes (nothing from SRS for example). You could also roll into any AutoZone and have the codes read for free. If you are looking to purchase a STAR computer, then you better start saving. They run around $25,000-30,000 and need to be updated every year (and that costs even more).
 
#4 ·
Well, except for the pre MY96 models, as the OP owns. The older OBD-I standard is not nearly so helpful as OBD-II and the code readers are harder to find and more expensive.

JenniferR, may I suggest you post in the 140 forum and see what those folks are using? I had a GM product that was OBD-I and there were two terminals you shorted and then it would flash the light to give you the code, then you look it up in a table. Don't know if that applies to Benz of your vintage, though.
 
#5 ·
Your car is OBDI with a 38 pin diagnostic connector and probably a built in LED / pushbutton for reading emission related codes. For about $10 in parts from Radio Shack you can build a code reader that will read the vast majority of the codes for the car. To me it's a requirement for owning a car from that era.
 
#8 ·
Interpret codes?



Thanks so much to everyone for your fabulous replies!
I was thinking of doing this. My husband is discouraging it. He says that I won't have any way to interpret the codes. He wants to take it to some place that charges $250 because he's under the impression that the free places don't interpret codes either. We are intelligent people with advanced degrees. I just don't understand how it could be that hard to find possible issues related to each code. For just 10 bucks it's worth trying but I'd like to keep my pride intact (and my husband's ego down to a reasonable level). If I'm wrong then I'll never hear the end of it! Any advice on interpreting codes would be greatly appreciated. Thanks again for all your help!
 
#6 ·
If you have an old laptop with an RS232 port laying around, buying a mutiplexer clone version of the Carsoft 7.4 SW may be a good investment. Carsoft can read data from most of the car modules and give you trouble codes and/or erase errors. Make sure you have a computer with a real built in RS232 port, a usb-rs232 or pcmcia-rs232 port adapter seldom works. expect to pay about $120 for clone version of carsoft 7.4
 
#9 ·
You'll be fine as long as your advanced degrees are in automotive technology. Just kidding. If you have any interest in getting engaged in the care of your car you should spend the 10 bucks and take a few minutes to learn how to do it. Some codes are self-explanatory, others can be researched here with the search function above or posted as a thread. I sent you a PM.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top