89 300 SE Check Engine Light & Buzzer niose

Does anyone other than MB Dealership have diagnostic equipment to tell me what the Check Engine Light problem is refering to? It came on the other day and the only thing I have noticed is a rough idle at start up...any suggestions on where to start and how to clear the check engine light? Thanks, Tim

I am also having trouble with a #8 8 Amp fuse blowing....The antenna is disconnected from the wiring harness and the fuse seems to last about 1/2 hour....there is also a low buzzing sound from the audible key in ignition ignition and lights on reminder buzzer when you put on the brakes....very annoying but goes away when the fuse is replaced, this fuse controls the door locks and several other items as well but the fuse does not blow when you lock the doors, the fasten seatbelt warning light flashes on and off when the fuse is blown as well. this one is driving me nuts....help!!!! Thanks again, Tim

Tim,

Check out Jim Forgione's website for a bit on how to read the trouble codes and reset the light. In particular, at the bottom of page

formatting link

is a schematic of acode reader you can make for less than $15 with radio shack parts. Thecodes were standardized from 1996 and on, and you can buy OBDII readersat Autozone and the like for those, but before that, you need to buildyour own. It has three leads to connect to the car, a push-buttonswitch to activate it, and an LED that blinks the codes at you. Unfortunately, he then wants to sell you a CD with a translation of what the codes mean! For that, go to

formatting link

a (large) .pdf file. I'm not sure what your connector looks like, but that manual has a decent summary of the different ones. On my 92 400E, I had a 38-pin connector, with about ten sockets populated. Two of them are power and ground, and the third wire goes to the pin corresponding to the system you are checking. Hold the button for 2 - 3 seconds to start to read codes. Reading codes involves just counting the times the LED blinks, and then correlating that with the right table in the .pdf manual. Then hit the button for 2 - 3 seconds to get the next code, and continue until the first one repeats. When you want to clear them, hold the push-button for more than six seconds.

Good luck with your fine car!

Gerry Visel

92 400E 87 300SDL 83 300TD 67 230, et al