Code result
P0136
O2 Sensor Circuit Malfunction
Moderate severity
What it means
A general fault has been detected in the downstream (post-catalyst) oxygen sensor on bank 1. The downstream sensor monitors catalyst efficiency rather than fuel mixture; with no signal, the catalyst monitor cannot run.
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
Downstream sensor aged
highOne of the most commonly reported causes for this code — check this first.
Wiring chafed against exhaust
mediumA plausible cause — test and verify before replacing parts.
Related help
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