Catalyst Temperature Sensor Circuit Low Bank 2 Sensor 1
What it means
P0437 means the catalyst temperature sensor on bank 2 (sensor 1) is reading an abnormally low voltage — usually a short to ground or an open in the circuit. This sensor monitors converter temperature for emissions control and doesn't affect how the engine runs, so the practical effects are a check-engine light and interrupted emissions monitoring.
Can I keep driving? The engine drives normally — this is a monitoring sensor, so the main consequences are a check-engine light and a possible emissions-test failure.
Real-world scan data
Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.
Common symptoms
What you'll notice
- Check-engine light on
- Possible failed or incomplete emissions readiness
- Usually no change in how the engine drives
Common causes
Most likely first
- Short to ground or low-voltage fault in the catalyst temperature sensor circuitLikely
- Faulty catalyst temperature sensor (bank 2, sensor 1)Common
- Chafed or pinched wiring grounding the signalCommon
- Poor or corroded connection at the sensorLess often
- Faulty ECM (least likely)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and confirm the fault is the bank 2 sensor 1 catalyst temperature sensor circuit low.
- Inspect the sensor's connector and wiring for a short to ground, chafing, or corrosion.
- Check the signal, reference, and ground at the sensor against specification.
- Compare the sensor's reading against actual exhaust temperature and the paired sensor.
- Repair the shorted wiring or replace the sensor as indicated. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0437?+
Can I just clear P0437?+
Related codes
Read & clear P0437 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.