Code result
P0157
O2 Sensor Circuit Low Voltage
Moderate severity
What it means
The ECU detects abnormally low voltage from the downstream O2 sensor on bank 2. Indicates persistently lean exhaust past the catalyst, open sensor or wiring shorted to ground.
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
Lean condition on bank 2
highOne of the most commonly reported causes for this code — check this first.
Signal wire shorted to ground
mediumA plausible cause — test and verify before replacing parts.
Downstream O2 sensor failed
mediumA plausible cause — test and verify before replacing parts.
Related help
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