P0052

HO2S Heater Control Circuit High Bank 2 Sensor 1

Q: Is it safe to drive with P0052?

Yes. The engine runs, though fuel trim can be slightly off until it warms up. Repair it before an emissions test and to avoid the small fuel-economy penalty.

Q: Can I just clear P0052?

It clears temporarily but returns when the ECM re-checks the heater circuit. The wiring or sensor fault has to be fixed for it to stay away.

Oxygen sensor heater Generic OBD-II Medium

What it means

P0052 means the ECM saw high voltage in the heater circuit of the Bank 2, Sensor 1 oxygen sensor — the upstream (pre-catalyst) sensor on bank 2. Its built-in heater lets the sensor start reading exhaust oxygen quickly so the engine can enter closed-loop fuel control. With the heater circuit faulted, the sensor warms up slowly, fuel trim can drift during warm-up, and the check-engine light comes on.

Medium

Can I keep driving? Yes — the car drives normally, but the upstream sensor reaches operating temperature slowly, so fuel trim may be off during warm-up and the check-engine light stays on.

Real-world scan data

Seen in

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

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
Failed or incomplete emissions test (readiness monitor won't set)
Slightly reduced fuel efficiency, mostly during warm-up
Occasionally rougher running until the engine is fully warm

Common causes

Most likely first

Failed oxygen sensor heater element (Bank 2, Sensor 1)Likely
Open or short-to-power in the heater control wiringCommon
Corroded or loose connector at the sensorCommon
Faulty ECM/PCM heater driver (rare — check wiring and sensor first)Less often

How to diagnose & fix

Work through it in order

Read freeze-frame data and confirm the fault is current.
Inspect the Bank 2 Sensor 1 connector and harness for corrosion, chafing, or a loose pin.
Measure heater element resistance and compare to the manufacturer spec.
Check for correct power and ground at the heater connector with the key on.
If wiring and power check out, replace the upstream oxygen sensor. Clear and re-test.

FAQ

Quick answers

Is it safe to drive with P0052?+

Yes. The engine runs, though fuel trim can be slightly off until it warms up. Repair it before an emissions test and to avoid the small fuel-economy penalty.

Can I just clear P0052?+

It clears temporarily but returns when the ECM re-checks the heater circuit. The wiring or sensor fault has to be fixed for it to stay away.

Read & clear P0052 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX