O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)
20 articles · 2 makes affected
What is P0155?
P0155 indicates a problem with the oxygen sensor heater circuit on Bank 2 Sensor 1, which can affect fuel efficiency and emissions. This is a medium-severity powertrain issue that commonly triggers the check engine light. Based on real data, this code appears frequently in Ford Mustangs, with repair costs averaging $2685.
Common Causes
- ●Faulty oxygen sensor heater element (most common cause)
- ●Damaged wiring or connectors in the O2 sensor circuit
- ●Blown fuse or relay for the O2 sensor heater circuit
- ●PCM/ECU issues affecting sensor power supply
Symptoms You May Notice
- ●Check engine light illuminated (universal symptom)
- ●Reduced fuel economy due to improper air-fuel mixture
- ●Possible rough idle or hesitation during acceleration
- ●Failed emissions test due to O2 sensor malfunction
How to Fix It
- ●Replace Bank 2 Sensor 1 oxygen sensor ($150-$400, moderate difficulty)
- ●Repair damaged wiring or connectors in O2 sensor circuit ($100-$300, moderate difficulty)
- ●Replace blown fuse or relay for heater circuit ($20-$100, easy)
- ●Diagnose and repair PCM/ECU issues ($500-$1500+, difficult)
Owner Statistics
Based on 11,449 real owner discussions • 708 confirmed solutions
About This Data
Statistics are aggregated from real owner discussions on Reddit, automotive forums, and YouTube comments. All data is anonymized and represents actual repair experiences reported by vehicle owners.
Frequently Appears With
These codes often appear together in owner reports. Check these if you see P0155.
Based on analysis of 8 owner reports where multiple codes appeared together.