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
Common Causes
Failed O2 sensor heater elementlikely
Blown fuse for O2 heater circuitpossible
Wiring damage to sensorpossible
ECM driver circuit failureunlikely
How to Diagnose P0030
- 1Check O2 heater fuse
- 2Measure heater circuit resistance
- 3Inspect wiring to sensor
- 4Test with scan tool live data
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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.