Heated Oxygen Sensor: Camry

Heated oxygen sensor on rear (firewall side) exhaust manifold may be referred to as bank No. 1 sensor No. 1. Heated oxygen sensor on front (radiator side) exhaust manifold may be referred to as bank No. 2 sensor No. 1. Heated oxygen sensor on the exhaust pipe behind catalytic converter may be referred to as bank No. 1 sensor No. 2.
To test the heater on the heated oxygen sensor, disconnect electrical connector from appropriate heated oxygen sensor and note heated oxygen sensor terminals. See Fig 1 and Fig 2-20.
NOTE: Electrical connector for heated oxygen sensor on exhaust pipe behind catalytic converter is located below driver's side front seat, below carpet near center console and contains a Dark Gray 4-pin electrical connector.
Using ohmmeter, check resistance between +B and HT terminals on electrical connector. See Fig 1 and Fig 2-20. Replace heated oxygen sensor if resistance is not 11-16 ohms at 68°F (20°C).
If problem exists in heated oxygen sensor, heater or wiring circuit, a Diagnostic Trouble Code (DTC) may be stored in the Engine Control Module (ECM). For diagnosis of DTC, see appropriate TESTS W/CODES article.

Fig 1: Testing Heater On Typical Heated Oxygen (Avalon & Camry) Sensor At Exhaust Manifold

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Fig 2: Heater On Heated Oxygen Sensor At Exhaust Pipe Test (Avalon)

Fig 3: Heater On Heated Oxygen Sensor At Exhaust Pipe Test (Camry)