P046B
Catalyst Temperature Sensor 1/2 Correlation Bank 2
Catalyst / emissions
Generic OBD-II
Medium
What it means
P046B sets when the two catalyst temperature sensors on bank 2 report readings that don't agree with each other the way the ECM expects. It's a sensor-correlation code, so it's almost always a failing temperature sensor, drift, or a wiring fault rather than a problem with how the car runs — but it will keep the catalyst monitor from completing.
Medium
Can I keep driving? Drivable — this is a monitoring fault with no immediate driving risk, but the catalyst monitor won't be ready and the car will fail an emissions test.
Common symptoms
What you'll notice
- Check-engine light on
- No noticeable change in how the car drives
- Catalyst readiness monitor not completing
- Failed emissions / smog test
Common causes
Most likely first
- Faulty catalyst temperature sensor 1 or 2 on bank 2Likely
- Sensor drift causing the two readings to disagreeCommon
- Damaged or corroded sensor wiring or connectorCommon
- Open or short between a sensor and the ECMLess often
- Actual exhaust temperature anomaly at one sensor (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and compare the two bank-2 catalyst temperature sensor readings with a scan tool — a warm engine should show both roughly tracking together.
- Inspect both sensor connectors and wiring for corrosion, chafing, or loose pins.
- Replace whichever sensor is reading out of range or lagging the other.
- If both sensors and wiring check out, verify there's no exhaust leak near a sensor, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P046B?+
Yes — this correlation code doesn't affect drivability. It mainly means the ECM can't trust the catalyst temperature data, so the emissions monitor won't pass until it's fixed.
Can I just clear P046B?+
You can clear it, but if the two sensors still disagree the code returns after the next drive cycle. Diagnose the sensor or wiring first.
Related codes
Often seen with P046B
Read & clear P046B yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX