HO2S Heater Control Circuit High Bank 2 Sensor 3
What it means
P0064 means the ECM has seen high voltage in the heater control circuit of the bank 2, sensor 3 oxygen sensor — a downstream sensor used mainly to monitor the catalytic converter. Because this sensor doesn't control fueling, the engine runs normally, but the fault sets the check-engine light and will keep the car from passing an emissions test until the heater circuit is repaired.
Can I keep driving? Safe to drive — this is a downstream sensor's heater circuit, so it affects emissions monitoring, not how the car runs.
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
- Will fail an emissions/readiness test
- No noticeable change in how the engine runs
Common causes
Most likely first
- Failed heater element inside the bank 2, sensor 3 oxygen sensorLikely
- Short to voltage or open in the heater control wiringCommon
- Blown O2 heater fuseCommon
- Corroded or loose sensor connectorLess often
- Failed ECM driver (least likely)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data, then inspect the bank 2, sensor 3 (downstream) O2 sensor connector and heater wiring.
- Check the O2 heater fuse and the heater circuit for a short to voltage or an open.
- Measure the sensor's heater resistance; replace the sensor if the element is out of spec.
- Consider the ECM driver only after the wiring, fuse and sensor test good. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0064?+
Can I just clear P0064?+
Related codes
Read & clear P0064 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.