P0030

Symptoms

• Check Engine light comes on
• Increased fuel consumption
• Unstable engine operation at idle
• Reduced engine power
• Rough engine operation during cold start
• Increased toxicity of exhaust gases

Causes

• Faulty oxygen sensor
• Broken or damaged wiring to the sensor
• Corrosion of sensor connectors
• Blown heater circuit fuse
• Engine control unit malfunction
• Short circuit in the heater circuit
• Poor contact in the sensor connector

How to Fix

1. Connect the diagnostic scanner and read the error codes
2. Check the oxygen sensor circuit fuses
3. Inspect the sensor wiring for damage
4. Check the resistance of the sensor heater (usually 2-14 Ohms)
5. Measure the supply voltage at the sensor connector
6. Check the integrity of the sensor ground wire
7. If necessary, replace the oxygen sensor
8. Clean connectors from corrosion and oxides
9. Reset error codes and take a test drive

Related codes

Error P0030 by Vehicle Brand