Code result
P0159
O2 Sensor Circuit Slow Response
Moderate severity
What it means
The ECU detects an abnormally high voltage from the downstream O2 sensor on bank 2. Indicates persistently rich exhaust past the cat, shorted sensor or wiring shorted to voltage.
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
Rich condition on bank 2
highOne of the most commonly reported causes for this code — check this first.
Signal wire shorted to voltage
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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