O2 sensor

[rlg4675]

Hello, My check engine light came on and I checked the code using the on board diagnostics. The code that came up as a 1221- O2 sensor. I bought a Bosch replacement one (with the correct plug) but the check engine light is still on and it throws the same code 1221. How do you turn the light off ? Do I need to buy a code scanner to do this ? Or will the on board system figure out that the O2 sensor is new and turn off the light?

[Yurick]

Yes,
You will need to reset the check engine light yourself by using either a reset tool or as you mentioned scanner.

[Jeron]

I'm not sure but it might clear itself. There a certain classes of codes that only leave the light on for 10-ish drive cycles then the light goes off. The code should remain in history but no light.

It sounds like yours is OBD-I. You may be able to clear all codes by disconnecting the battery and reseting everything by touching the battery cables together for 5 seconds.

[rlg4675]

Yes its a 1994 325i

[rlg4675]

Sweet , I unhooked the bat waited then touched both unhooked cables together and......----- vola it worked !

Thank You all so much

[Yurick]

Cool,
I guess we both learned something new today - Thanks Jeron.

[Jeron]

I'm glad it worked for you.

Be aware you wont pass inspection after a reset (any type of reset) until you have driven the car the minimum number of drive cycles. A week of daily driving should be plenty.

[rlg4675]

Ok ,I will keep that in mind. I don't need a inspection for smog until December of '08 so that should be plenty of time. Once again ... Thank You!!!