P0030
Low SeverityHO2S Heater Control Circuit (Bank 1, Sensor 1)
Emissions System
What Does P0030 Mean?
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.
Common Fix
Replace upstream O2 sensor bank 1
Estimated Cost (DIY)
$30 - $100
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
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Related Resources
Repair guides, symptom pages, and wiring diagrams related to P0030.
Related Symptoms
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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
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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.
Related Repair Guides
If your vehicle has triggered P0030, these DIY repair guides may help: