I am guessing your car is obd0.
If it is, on the passenger side floor under the dash, there will be a plate under the carpet with a whole in it. There will be a red LED that flashes codes. You do not need a jumper to check the codes on the obd0 vehicle.

Concerning the o2 sensor, you can only disable the o2 sensor by removing it in your engine computer's programming. This would require you to have your computer socketed/chipped.