P043C
Catalyst Temperature Sensor Circuit Low Bank 2 Sensor 2
Emissions / catalyst monitoring
Generic OBD-II
Medium
What it means
P043C means the signal from the bank 2, sensor 2 catalyst temperature sensor is reading too low — usually a short-to-ground, a wiring fault, or a failed sensor. This sensor lets the ECM watch and protect the catalytic converter's temperature. The engine still runs normally, but the fault should be repaired so monitoring works correctly.
Medium
Can I keep driving? Safe to drive in the short term — this is a monitoring-sensor fault, not a running fault, though it should be fixed so the catalyst can be properly protected and monitored.
Common symptoms
What you'll notice
- Check-engine light on
- Often no noticeable change in how the car drives
- May fail an emissions or readiness test
Common causes
Most likely first
- Short-to-ground or low-voltage fault in the sensor's wiring or connectorLikely
- Faulty catalyst temperature sensor (bank 2, sensor 2)Common
- Corroded or damaged sensor connectorCommon
- Wiring chafed against the exhaust or chassisLess often
- Failed ECM (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data to confirm the fault is on bank 2, sensor 2.
- Inspect the sensor's wiring and connector for a short-to-ground, chafing, or corrosion.
- Measure the sensor's resistance and signal against the service spec.
- Replace the catalyst temperature sensor if it reads out of range, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P043C?+
Yes, in the short term. It reports a fault in a temperature-monitoring sensor, not an engine-running problem, but fix it so the catalyst stays protected.
Can I just clear P043C?+
You can, but it returns until the wiring or sensor is repaired, since the ECM keeps reading the low-voltage signal.
Related codes
Often seen with P043C
Read & clear P043C 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