Code result
P0142
O2 Sensor Circuit Malfunction
Moderate severity
What it means
The ECU detects an electrical fault in the heater circuit of the downstream oxygen sensor on bank 1. The heater current is out of range, suggesting an open or shorted heater element, blown fuse or wiring fault.
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
Sensor heater element open
highOne of the most commonly reported causes for this code — check this first.
Heater fuse blown
mediumA plausible cause — test and verify before replacing parts.
Heater wiring or connector fault
mediumA plausible cause — test and verify before replacing parts.
Related help
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