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2004 Chevy Avalanche P0156 and P0157 Fault Codes: O2 Sensor Issues Explained

Model: 2004 Chevy Avalanche Fault Code: P0156 Posted: 2016-08-12 13:16

I'm currently experiencing fault codes P0156 and P0157 on my 2004 Chevrolet Avalanche with a 5.3L V8 engine (VIN T, automatic transmission). The codes indicate issues with the oxygen sensor in Bank 2, Sensor 2. Specifically: - P0156: HO2S Performance - Bank 2, Sensor 2 - P0157: HO2S Circuit Low Voltage - Bank 2, Sensor 2 Possible causes include a faulty oxygen sensor, shorted signal to ground, wiring problems due to exhaust component contact, or holes in the exhaust system near the sensor. I'm looking for advice on diagnostics and potential fixes.

Related fault codes
P0156
Comments (2)
Anonymous 2016-08-12 13:25

I'm also seeing P0156 and P0157 codes on my 2004 Chevy Avalanche with a 5.3L V8 (VIN T, automatic). The issue appears to be related to the oxygen sensor in Bank 2, Sensor 2.

Anonymous 2016-08-12 15:11

Using an OBD2 scanner, I checked the B2S2 voltage reading — it's inconsistent and below expected levels. Are there any other diagnostic codes present? Any modifications made to the exhaust or engine system? P0156 (5.3L V8 VIN T Auto): HO2S Performance - Bank 2 Sensor 2 P0157 (5.3L V8 VIN T Auto): HO2S Circuit Low Voltage - Bank 2 Sensor 2 Possible causes: • Faulty oxygen sensor • Signal shorted to ground • Wiring issues due to contact with exhaust components • Holes in the exhaust system near the O2 sensor