P0030
Low SeverityHO2S Heater Control Circuit (Bank 1, Sensor 1)
Emissions System
P0030 — Instant Answer
HO2S Heater Control Circuit (Bank 1, Sensor 1)
Severity: LOW SEVERITY
Meaning: The oxygen sensor heater circuit on the upstream (pre-cat) sensor of bank 1 has a fault. The heater gets the O2 sensor to operating temperature quickly for proper fuel trim.
Safe to drive? Usually yes with caution, but confirm root cause before long trips.
Estimated repair cost: $30 - $100
Most common causes:
- 1. Failed O2 sensor heater element (35-45% of cases)
- 2. Blown fuse for O2 heater circuit (10-25% of cases)
- 3. Wiring damage to sensor (10-25% of cases)
- 4. ECM driver circuit failure (5-10% of cases)
Symptoms
- ⚠️Check engine light
- ⚠️Slightly increased fuel consumption
- ⚠️Failed emissions test
- ⚠️Longer warm-up period
Related Symptoms
Common Causes
How to Diagnose P0030
- 1Check O2 heater fuse
- 2Measure heater circuit resistance
- 3Inspect wiring to sensor
- 4Test with scan tool live data
OEM Diagnostic Flowchart
Scroll to load technician if/then branches.
Read live data and freeze frame for P0030 to pinpoint the cause before buying parts.
TopScan
$51.27
DIYers who want phone-based scanning
View on TOPDON
ArtiLink600
$99
DIYers working on ABS/airbag systems
View on TOPDONGot a repair estimate for P0030? Check if the quote is fair before ordering parts.
Turn This Into a Confident Next Step
Verify the likely fault first, then compare a quote before you approve expensive work.
Affiliate disclosure: We may earn a commission at no extra cost to you.
View supporting tool options
OBD2 scanner
Read codes and freeze-frame data before you guess at the fault.
Most diagnostic jobs start with a scan tool and a verified code path.
Shop on Amazon →Battery tester
Check cranking and charging health before replacing expensive parts.
A weak battery can mimic alternator or starter problems.
Shop on Amazon →Multimeter kit
Confirm voltage, continuity, and sensor power with one simple kit.
A meter is the cheapest way to rule out a bad circuit fast.
Shop on Amazon →Ready to fix it yourself?
Find My Vehicle Repair Guide →Select your exact vehicle for a personalized step-by-step guide
Related Resources
Repair guides, symptom pages, and wiring diagrams related to P0030.
Related Symptoms
Browse →Exact Vehicle Hubs
Browse →Open the exact vehicle hub for a repair workflow commonly associated with P0030.
Open the exact vehicle hub for a repair workflow commonly associated with P0030.
Open the exact vehicle hub for a repair workflow commonly associated with P0030.
Open the exact vehicle hub for a repair workflow commonly associated with P0030.
Open the exact vehicle hub for a repair workflow commonly associated with P0030.
Open the exact vehicle hub for a repair workflow commonly associated with P0030.
Exact Repair Workflows
Browse →Open the exact repair flow most commonly associated with P0030 on this vehicle.
Open the exact repair flow most commonly associated with P0030 on this vehicle.
Open the exact repair flow most commonly associated with P0030 on this vehicle.
Open the exact repair flow most commonly associated with P0030 on this vehicle.
Open the exact repair flow most commonly associated with P0030 on this vehicle.
Open the exact repair flow most commonly associated with P0030 on this vehicle.
Related Codes
The O2 sensor heater circuit voltage is lower than expected on the upstream bank 1 sensor. Usually means an open circuit in the heater element.
The heater in the upstream O2 sensor on bank 1 is not working properly. The heater brings the sensor to operating temperature quickly.
The heater circuit for the downstream (post-cat) O2 sensor on bank 1 has failed. This sensor monitors catalytic converter efficiency.
Frequently Asked Questions
- Can I drive with P0030?
- Yes, it is safe to drive. The only effect is slightly worse fuel economy during warm-up and a failed emissions test.
- How do I fix P0030?
- Check the O2 heater fuse first. If the fuse is good, the O2 sensor heater has failed and the sensor needs replacement.
Get the Complete Maintenance Schedule for P0030 drivers
Oil, filters, belts, brakes, and fluid intervals sent to your inbox. Unsubscribe anytime.
Not sure you want to DIY? Compare local shop pricing first.
Author & Review
Written by AllOEMManuals Editorial Team. Reviewed by ASE-certified technicians and updated with factory-reference checks for fitment-sensitive steps.
This guide was drafted with AI assistance and reviewed for accuracy by a human editor.
Last updated: 2026-05-07