HO2S-21 (Bank 2 Sensor 1) Circuit High Input
3 remaining possible causes after you changed both o2 sensors.
HO2S signal tracking (due to oil or moisture in the connector). Check carefully the connector.
HO2S signal circuit is open or shorted to VREF
( check for short in the HO2S signal circuit)
PCM has maybe failed
let me know if you further questions.
Thursday, September 24th, 2009 AT 4:32 PM