To verify the fault, a Lambda test would verify that the O2 sensor is bad. If it's shorted, then the meter would deflect full scale. Your air/fuel mixture is not correct if it is defective.
For my car ('94), code '17' is a "Data exchange malfunction between individual control modules". Are you sure that the DTC is an O2 sensor?
Also my car uses a 'heated' O2 sensor. This supplies 12V bias to ensure that the sensor sees a constant operating temperature. I suppose it could short out causing your fault.
Again a Lambda test will show how good it is. It's physically located on the exhaust headers so it may be removable from the top side. My is NOT, only from underneath.
[Edited by JimF on 05-09-2001 at 03:29 PM]
Regards . . . . JimF
'94 S500 Cpe
Visit my Mercedes Web Page