Heated Oxygen Sensor Heater Control Circuit High (Bank 1, Sensor 3)
The P0044 code means the vehicle's onboard diagnostic system has detected: Heated Oxygen Sensor Heater Control Circuit High (Bank 1, Sensor 3). This is a low severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- moderate
- Estimated cost
- $100 - $300 (parts and labor)
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Common Symptoms
- Check Engine Light on
- Slight decrease in fuel economy
- Possible emissions test failure
- No noticeable drivability issues in most cases
Probable Causes (Ranked by Likelihood)
- Short circuit in O2 sensor heater wiring Very High
- Internally shorted O2 sensor heater element High
- Faulty ECM heater control driver Moderate
- Water intrusion into sensor connector Moderate
Frequently Asked Questions
What does P0044 mean?
P0044 indicates a high voltage condition in the heater circuit of the Bank 1 Sensor 3 oxygen sensor, usually caused by a short circuit in the wiring or sensor.
Can I pass emissions with P0044?
Likely not. Most emissions tests will flag any active Check Engine Light code, including P0044. The sensor heater issue needs to be resolved before testing.
What is the typical repair for P0044?
The typical repair involves replacing the oxygen sensor or repairing a short circuit in the heater wiring. Costs range from $100 to $300.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Confirm P0044 with scan tool
-
Inspect wiring to Bank 1 Sensor 3 for shorts or damage
-
Measure heater circuit resistance and compare to specifications
-
Check for water intrusion or corrosion at the O2 sensor connector
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
Commonly Affected Vehicles
- 2008-2017 Honda Pilot
- 2010-2019 Toyota Highlander
- 2009-2018 Lexus RX350
- 2007-2016 Acura MDX
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