Quick takeaway: repairs for P015B typically involve the downstream O2 sensor heater circuit (Bank 2 Sensor 2). In most cases you’re looking at roughly $100 to $400 for parts and labor, plus a diagnostic fee of about $80 to $120 if it isn’t included in the repair. More complex wiring or ECU issues can push the total higher.
What P015B Means
P015B is an OBD-II diagnostic trouble code that points to a fault in the heater circuit of the downstream oxygen sensor on Bank 2, Sensor 2. The sensor’s heater helps it reach operating temperature quickly, allowing accurate readings of exhaust gases. When the heater circuit fails, the sensor may run cooler than intended, potentially hindering catalytic efficiency and emissions control.
Common Causes
There are several plausible explanations for a P015B code. The following list covers the most frequent scenarios technicians encounter.
- Faulty downstream O2 sensor (Bank 2, Sensor 2) itself
- Damaged or corroded wiring or connector for the heater circuit
- Blown fuse or relay that powers the O2 sensor heater
- Short to voltage or ground in the heater circuit
- Poor ECU/PCM control or other electrical faults affecting the circuit
Because the heater circuit issue can stem from several different sources, a shop will typically perform targeted tests (live data readings, resistance checks, and wiring inspection) to confirm the exact cause before replacing components.
Cost Breakdown and Estimates
Prices vary by vehicle make/model, location, and whether you choose OEM or aftermarket parts. The figures below reflect typical U.S. shop pricing reported in 2024–2026 and assume the repair is limited to the heater circuit issue without unrelated engine failures.
Here is a practical cost guide to consider when budgeting for P015B repairs. The ranges account for parts and labor, and assume a straightforward sensor-related fix rather than more extensive electrical work.
- Downstream O2 sensor (Bank 2 Sensor 2) replacement: Parts range from about $60 to $250 for aftermarket sensors and $150 to $350 for OEM sensors. Labor is typically 0.6 to 1.2 hours at a shop rate of roughly $80 to $130 per hour. Total estimate: about $150 to $450 for aftermarket parts, or $250 to $500+ for OEM parts.
- Wiring/connector repair or fuse/relay issue: Parts may be $0 to $150 (depending on whether wiring repair kits or new connectors are needed). Labor often runs 1 to 2 hours. Total estimate: about $120 to $400, plus any diagnostic fee.
- ECU/PCM-related electrical fault (less common): Diagnostic time plus possible component repair or replacement. Total estimate: roughly $200 to $1,000 or more, depending on parts and whether programming is required.
In most cases, replacing the downstream O2 sensor is the most cost-effective fix when the heater circuit is at fault. However, a precise diagnosis is essential to avoid unnecessary work or misdiagnosis.
What to Expect at the Shop
Understanding the repair flow can help you budget and talk with your technician effectively. The following steps outline a typical repair path for a P015B diagnosis.
- Diagnostic confirmation: The mechanic will verify the P015B code with a scan tool, check live sensor data, and inspect the heater circuit (power, ground, and resistance).
- Repair decision: Based on findings, they’ll determine whether to replace the downstream O2 sensor, repair wiring/connectors, or address a broader electrical fault.
- Component replacement or repair: If the sensor is faulty, it will be replaced. If wiring or a fuse/relay is at fault, those components will be repaired or replaced as needed.
- Post-repair testing: After the fix, the system will be re-scanned, and a road test or drive cycle will be performed to confirm the code does not return and that emission monitors are ready.
- Documentation and warranty: You should receive a detailed invoice, warranty information for replacement parts, and notes on any follow-up checks (if applicable).
Note that some shops may offer a diagnostic fee regardless of the final repair, so ask about pricing up front. If a repair involves the ECU or programming, it may require additional time and costs.
Summary
For P015B—the bank 2 sensor 2 oxygen sensor heater circuit—the typical repair path is most often the replacement of the downstream O2 sensor or the wiring associated with its heater. Expect a cost range of about $100 to $400 for a standard sensor replacement with labor and parts; diagnostic fees can add $80 to $120 if not included. More complex electrical issues, such as wiring harness problems or ECU-related faults, can push the total higher, sometimes into the $500–$1,000 range or more depending on the scope and vehicle. A precise diagnosis is key to controlling costs and ensuring the right fix is performed.