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P0030MinorEmissions

P0030 on 2009-2018 Subaru Forester (Base, Premium, Limited, Touring, XT) — HO2S Heater Control Circuit (Bank 1 Sensor 1)

1 vehicles · 1 makes · $150-$450 repair

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Most Reported On

2009-2018Subaru ForesterBase +4

P0030 is an OBD-II diagnostic trouble code meaning “HO2S Heater Control Circuit (Bank 1 Sensor 1).” The PCM detects a fault in the heater control circuit of the heated oxygen sensor (HO2S) at Bank 1, Sensor 1 (upstream). The internal heater that brings the sensor to operating temperature is not responding as expected. This code is most commonly reported on 2009-2018 Subaru Forester (Base, Premium, Limited, Touring, XT), with repair costs ranging from $150 to $450.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (1)
  • Related Codes
  • FAQ
  • Sources (2)
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Common Causes

1Failed O2 sensor heater element
2Blown fuse or open in heater circuit
3Corroded/loose connector
4PCM heater driver fault

Typical Repair Cost

$150 - $450

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P0030, you'll need an OBD-II scanner. Here are our recommendations at every price point.

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Vehicles Affected (1)

Subaru P0030 page →
ForesterMinor

Front Air/Fuel Ratio (Wideband O2) Sensor Heater Circuit Failure — P0031/P0037

2009-2018$150-$4500 reports

Related Codes (8)

P0031HO2S Heater Control Circuit Low (Bank 1 Sensor 1)P0032HO2S Heater Control Circuit High (Bank 1 Sensor 1)P0033Turbocharger/Supercharger Bypass Valve Control Circuit/OpenP0034Turbocharger/Supercharger Bypass Valve Control Circuit Low01447EVAP System (VAG)P0040O2 Sensor Signals Swapped (Bank 1 Sensor 1 / Bank 2 Sensor 1)P0041O2 Sensor Signals Swapped (Bank 1 Sensor 2 / Bank 2 Sensor 2)P0042HO2S Heater Control Circuit (Bank 1 Sensor 3)

FAQ

What does P0030 mean?

P0030 stands for "HO2S Heater Control Circuit (Bank 1 Sensor 1)." The PCM detects a fault in the heater control circuit of the heated oxygen sensor (HO2S) at Bank 1, Sensor 1 (upstream). The internal heater that brings the sensor to operating temperature is not responding as expected.

What are the most common causes of P0030?

The most common causes of P0030 are: Failed O2 sensor heater element, Blown fuse or open in heater circuit, Corroded/loose connector, PCM heater driver fault. The specific cause varies by vehicle.

How much does it cost to fix P0030?

Repair costs for P0030 range from $150 to $450, depending on the vehicle and root cause.

Which vehicles are affected by P0030?

Au7o has documented P0030 across 1 vehicle models from 1 manufacturers: Subaru.

Sources (2)

  • Forum2014 Oxygen sensor codes P0031 P0037 — Subaru Forester Owners Forum
  • articleSubaru Forester P0037: O2 Sensor Heater Control Circuit Low (B1S2) — Drivetrain Resource
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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