P1051
HO2S Heater Current Monitor Circuit High (Ford)
Moderateoxygen sensor
Overview
The P1051 diagnostic trouble code indicates a ho2s heater current monitor circuit high (ford) condition. Oxygen sensors monitor the oxygen content in the exhaust stream and provide feedback to the PCM for precise fuel mixture control. A malfunction in the O2 sensor circuit can result in poor fuel economy, increased emissions, and potential catalytic converter damage.
Symptoms
- Check Engine Light (MIL) illuminated
- Rough idle or engine hesitation
- Failed emissions test
- Poor fuel economy
Common Causes
- Faulty PCM (Powertrain Control Module)
- Incorrect sensor installed
- Failed or aging oxygen sensor
- Damaged O2 sensor wiring or connector
Diagnosis Steps
- 1Connect an OBD-II scanner and read all stored trouble codes and freeze frame data
- 2Monitor the O2 sensor readings using live data on the scan tool
- 3Inspect the O2 sensor wiring and connector for damage or corrosion
- 4Test the O2 sensor heater circuit with a multimeter
- 5Check for exhaust leaks near the O2 sensor location
Estimated Repair Cost
$100 — $400
Cost varies by vehicle, location, and repair shop. Includes parts and labor.
Commonly Affected Vehicles
Chevrolet MalibuHyundai ElantraHonda CivicMazda 3
Related Codes
More Oxygen Sensor Codes
P0030HO2S Heater Control Circuit (Bank 1 Sensor 1)
ModerateP0031HO2S Heater Control Circuit Low (Bank 1 Sensor 1)
ModerateP0032HO2S Heater Control Circuit High (Bank 1 Sensor 1)
ModerateP0036HO2S Heater Control Circuit (Bank 1 Sensor 2)
ModerateP0037HO2S Heater Control Circuit Low (Bank 1 Sensor 2)
LowP0038HO2S Heater Control Circuit High (Bank 1 Sensor 2)
ModerateFrequently Asked Questions
Most O2 sensors should be replaced every 60,000-100,000 miles as preventive maintenance. Heated O2 sensors may last longer, but performance gradually degrades with age.