- Oct 18, 2012
- 157
It says o2 sensor heater issue, I changed the fuse and the sensor (both of them) are brand new. I don't know what else to Check honestly, any ideas to fix this code?
Wooluf1952 said:Did you use a Bosch O2 sensor?
blackout51 said:Yes I did, upstream and downstream
blackout51 said:Yes I did, upstream and downstream
the roadie said:That's the issue. It's more of a GM issue than a problem with the Bosch sensor, but here's the detail. The sensor side of the unit is fine. No issues with Bosch sensors. HOWEVER, the heated O2 sensor also includes an electric heating element to get it up to working temp (like a diesel glow plug) when you first start. The GM PCM programmers wanted to detect a problem with an open or shorted heater circuit, so they put a current sensing circuit in the PCM. The Delco unit's heater is closer to the center of the max/min limits for this parameter, so it almost never fails. The Bosch units were made with a normal current closer to one of the limits. With normal manufacturing variation, some of them work, and some of them are just over the limit and fail. Their function is fine, and they operate in closed loop mode exactly as intended. Just the heater current is a little bit off. The GM limits IMHO are tight on purpose to "encourage" people to use the Delco sensors and shun the Bosch. But that's my paranoid side thinking.
"There is also a potential for damaging the computer and/or oxygen sensor if a multiwire universal sensor is connected incorrectly."