P0161 – HO2S Heater Performance Bank 2 Sensor 2: The Powertrain Control Module (PCM) supplies a bias voltage (approximately 450 mV) on the Heated Oxygen Sensor (HO2S) signal high and low circuits.

Question:I have a 2003 Toyota Sequoia with the 4.7-liter engine and about 85,000 miles. It runs fine, but the Check Engine light came on, and I had the codes read by a friend with a scanner. It was ...

P0134 – O2 Sensor Circuit No Activity Detected Sensor 1 Bank 1: The front heated oxygen sensor (or O2 sensor 1) is placed into the exhaust manifold. It detects the amount of oxygen in the exhaust gas ...