1997 S500 Code Scanner
 

I just bought a 1997 S500, black on black. Very nice body paint and interior, but has several dash lights on, outside light (should be easy to find and replace whatever bulb is burnt out), SRS, ABS/EPS. Plus the oil pressure gauge shows zero when the car is cruising. When idling the gauge will show about 2 bars, then begin to rise as the engine speed increases. Just at the point when it would hit the top, 3, it drops to zero. I'm not too concerned as I'd been test driving the car for an hour before I noticed it and it ran perfectly, no engine noise, overheating or bad smells.

Anyway, my first thought is to replacing the oil pressure sending unit. Are the oil pressure gauges known to be a problem on these cars?

Can I use my OBD2 scanner with ths car, and will it read the codes for whatever is causing the SRS, ABS/EPS lights to be on.

Finally, where can I find a list of this car's codes?

Thanks, owning this scares me a bit as I know from reading the forum that it's a complex beast. My good old '89 300se is so reliable I hate to sell it but there's only room for so many cars in my life. ;-)

You can get some basic info on the OBD scanner but to read all of them you need to hook one of the MB type scanners to it. You can probably pick something up on ebay that will suit your needs for just your application.

Your car is OBD-II compliant, so any OBD-II code reader will read the normal codes, and most will also read the manufacturer-specific ones. The codes are all over the internet as well.

However. (There's always one of those, right?)

A normal OBD-II reader will only clear the normal codes...and ABS, SRS etc. are not normal codes. ;)

For advanced diagnostics (and to clear the others) you need something compatible with MB's system. Obviously the $$SDS$$ will do that, but there are other alternatives, including Carsoft. These require dedicated Windows laptops with serial connections to a proper interface for the 38-pin diagnostic connector under the hood. They are also more costly. :)

The ABS/EPS error may simply be a bad brake light switch. That is pretty common, and it's inexpensive and easy to replace. Source it at the dealer to make sure you get a genuine part, the aftermarket ones seem to be pretty buggy.

If SRS is a hard code, it's going to have to be reset by the proper interface and the source of the error needs to be corrected. (The passenger seat pad is a common failure point). If it's not a hard code it will otherwise reset with a battery disconnect (once it's disconnected, step on the brake pedal for thirty seconds to dissipate stored energy). This will trigger some additional alerts on restart related to the steering angle sensor, cranking the wheel lock-to-lock a few times and then restarting the car will clear them. You will also need the radio code, and to reset windows, etc. (covered in your owners' manual).

So if the battery disconnect and resets doesn't clear the SRS error, you'll need the more advanced interface to clear it, and that should also point at the source of the failure.

Hope that helps and good luck. Also, welcome to the club of MB ownership. :D

Thanks very much! Great information. This isn't my first MB, but it's far and away the most sophisticated. The first was an '83 380SEL, followed by an '89 300 SE, which I still have. The 83 had been badly neglicted and after two years of pouring money into it I sold it for the same price I paid. I made a more careful selection with the second one, thanks to the great advice I got from the forum and it still looks, starts, idles and runs beautifully at more than 229,000 miles.

ESP/ABS warning lights fixed.
 

I searched the forum archives for an answer to my ESP/ABS warning lights coming on and going off. The suggestion was to replace the brake light switch with an OEM. I did that and it resolved the problem. At first we thought it wasn't fixed as when the car was first stated the lights were still, but by the time I got it out of the parking lot they went off and have not come back on!

Sounds like a great car! Just out of curiosity and because I've been thinking over the last few years about getting a S600, S500 , or a 300SD (140 chassis). How much did you pay for the newest addition?

I wasn't really looking to buy a new a car, as my '89 300SE still looks good, runs perfect and everything, right down to the dash clock, still works, but a local general auction house had a '95 S420 coming up with 65,000 miles on it and I thought it might go cheap. I looked at it and it was near perfect but the auction estimate was 8 to 10 thousand, which was more than I wanted to pay. However, during the process, I did some research on eBay, Craig's List, Kelly Blue book etc. to see what they were going for and I found this '97 S500 with 110,000, one owner on Craig's List listed at an asking price of $5900 which I thought was very low. I drove it and it was nice so I did a bit of dickering with the owner, and wound up buying it for $4800. It even came with a set of newly new Bridgestone Blizzaks as an extra!

Anyway, it has a few issues as you can see from my posts, but I'm working through them without spending too much, the biggest expense being new discs and pads all around. Hopefully I'll have it all sorted out for around a grand.

It's a great car to drive, huge power and excellent handling, loaded with nice features and lovely to look at. It's also black on black, my favorite. It's a little scary though, very complex and can be expensive to make right when things go wrong, still I'm very happy to have it. My biggest problem is deciding what to do with my 300SE. It's still a very nice car, so I hate to let it go, especially if it went cheap, but we have 2 drivers and 5 cars so it's kinda hard to keep them all.