P0155
02 Sensor Heater Circuit Malfunction
Description
02 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1) This body system diagnostic trouble code indicates an issue with the vehicle's comfort, safety, or convenience systems.
OBD Codes Details
Possible Causes
Blown fuse, faulty switch, damaged wiring harness, poor electrical connection
Solution
Check fuses and relays, inspect wiring harness, test switches and sensors, repair damaged circuits
Symptoms
- Check engine light illuminated
- Rough idle or hesitation
- Poor fuel economy
- Engine running rich or lean intermittently on bank 2
- Failed emissions test
Diagnostic Recommendations
- Inspect O2 sensor wiring and connector for bank 2 sensor 1
- Test O2 sensor signal voltage with a scan tool
- Check for exhaust leaks upstream of the sensor on bank 2
- Verify sensor heater circuit resistance
- Replace O2 sensor if readings are out of range
Repair Cost Estimate
- O2 sensor replacement (upstream, bank 2): $150-400
- Wiring/connector repair: $80-200
- Exhaust leak repair: $100-300
- Diagnostic scan: $80-150
- Total diagnostic and repair: $150-700
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Fact-checking completed
Verified by:
Pavel Volkov
Created:
Last updated:
Information verified against official sources
Official Sources
Society of Automotive Engineers
Official OBD-II diagnostic trouble codes standard (SAE J2012)
Automotive engineering standards organization
International Organization for Standardization
International standard for vehicle diagnostic systems
International standards for automotive diagnostics
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