Code result
P2B89
Intake Air O2 Sensor Circuit Low Voltage Bank 1
Moderate severity
What it means
Voltage on the intake air oxygen sensor signal line on bank 1 is below the expected window. A drifted or sluggish lambda sensor lets the mixture run lean or rich without correction — fuel economy and emissions suffer immediately.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Signal wire shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Internal sensor short
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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