P0154 O2 Sensor No Activity Circuit - 2006 Harley-Davidson Street Bob Diagnosis

Model: H-D Street Bob Fault Code: P0154 Posted: 2012-07-02 18:26

I own a 2006 Harley-Davidson Street Bob and am encountering the P0154 diagnostic trouble code, which reads 'O2 Sensor No Activity Circuit'. This error appears during engine diagnostics and causes the check engine light to illuminate most frequently when riding in 6th gear. It occasionally activates in 5th gear when I exceed 75 mph—my maximum speed in that gear—which I only reach to avoid triggering the warning light. Since I have limited experience with bike maintenance, I'm seeking clarity on what might be causing this issue and why it specifically occurs in 6th gear. I've tried searching online forums but haven't found a definitive explanation. Any insights into possible causes or diagnostic steps would be greatly appreciated.