Powertrain
Definition only
Lights the check engine lamp
P237A: O2 Sensor Exhaust Sample Error Bank 1 Sensor 2
Standardized SAE J2012 code · P23xx — Ignition system and misfire
What does P237A mean?
O2 Sensor Exhaust Sample Error Bank 1 Sensor 2: the control module has detected this fault condition. (Code P237A)
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
Common causes
- High Sensing element or protective tube fouled with soot, oil or coolant
- Medium Sensor seal or thread leaks - bypass air dilutes sample
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P237A on the same make and model first.
P237A in the community
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