Two quesions actually: (1991 300E)

First: I took my car in to get the CEL read, and they said it was a faulty oxygen sensor. I replaced the oxygen sensor today, and everything went well. My question is this: is there anyway to clear the Check Engine Light so I can assure myself that i fixed the problem (if the light stays off)? I'd rather not have to take it in to get cleared as I'm sure they would figure out someway to charge me something.

Second: Is there anything i need to adjust, or change after installing a new oxygen sensor?

Thanks in advance.
-E

 

To clear the CE lamp you need to interrogate the fault via the X11 diagnostic connector. This is the round plug on the driver-side wheel well in the engine compartment. If you do not know how to use the pulse readout, let me know and I will explain it.

You should not have to adjust anything after installing the new O2 sensor, but you might want to check the lambda (fuel/air mixture) with the new sensor installed. You need to hook up a multimeter on the duty cycle setting to X11.

 

Is there a way to check the codes without any special equipment? People keep telling me to use the self diagnostic LED, but i didn't think the 103's had that...