2005 GMC Yukon 6.0L Engine P0054, P0137, P0141 O2 Sensor Fault Diagnosis and Fix
I've been experiencing persistent emissions issues with my 2005 GMC Yukon equipped with a 6.0L V8 engine. After replacing the driver's side catalytic converter, which resolved the P0420 code, I'm now seeing new trouble codes: P0054, P0136, and P0141. These codes are all related to the same oxygen (O2) sensor—Bank 1, Sensor 2. Specifically: - P0054: HO2S Heater Resistance Fault - Bank 1, Sensor 2 - P0137: HO2S Circuit Low Voltage - Bank 1, Sensor 2 - P0141: HO2S Heater Performance Fault - Bank 1, Sensor 2 I'm looking for reliable guidance on diagnosing and fixing these issues to avoid further repair costs. The check engine light remains on, which is causing ongoing frustration. Any insights or troubleshooting steps would be greatly appreciated—especially regarding sensor replacement quality (e.g., AC Delco) and whether the oxygen heater circuit might be faulty.
First suggestion: keep your system stock if possible. AC Delco sensors are commonly used in 6.0L GMC Yukon vehicles. Are there any additional diagnostic codes or performance issues present? The three codes—P0054, P0137, and P0141—all point to the same sensor (Bank 1, Sensor 2). If this sensor was recently replaced, ensure it was an original equipment manufacturer (OEM) or high-quality aftermarket part like AC Delco. Key areas to investigate: - Check for proper heater circuit function in the O2 sensor—both P0054 and P0141 relate to heater performance and resistance. A faulty heater circuit can cause inaccurate readings and trigger these codes. A failing heater circuit may result in poor sensor response, leading to incorrect air-fuel ratio feedback and emissions failure. Testing with a scan tool or multimeter is recommended to verify voltage and resistance values.