I just bought a 2001 xtreme blazer has 160k. I tuned it up and it runs great. I got a code p0155 heater malufunction bank 2 sensor 1. I replaced the pass side sensor before the Y with a standard brand green box. Never had a problem with their sensors. AC delco are hard to find in the stores everybody has that crap bosch stuff. Anyway the light didn't go off after I changed the sensor. Should it go off if the problem is fixed or must it be reset?

 

To start diagnosing this problem, I would have first swapped sensors side to side. If the code follows the sensor, then replace the sensor. Since we are past that, you have a decision to make. And that is is the new sensor good or is it a problem with the wiring.

 

What I was wanting to know is should the light shut it self off or does it have to be reset. I still have the other sensor and can swap it but it is a little dark out now.

 

It should go away if the fault is repaired. How long ago did you replace the sensor?

 

I just changed it tonight. Bank 2 is the pass side correct? I have seen it refered to as the drivers side. I was always told bank one has cyl 1 and bank 2 has cyc 2 on it.

 

You are correct. If the new sensor did in fact fix the problem, then the light should go out after 3-4 drive cycles.