Technical Definition:

O2 Heater Circuit (Bank 1, Sensor 2)

Technical Description:

The heated circuit in the oxygen sensor on bank 1 decreases time needed to enter closed loop.

Possible Causes:

• open or short to ground in the wiring harness
• O2 heater circuit wiring high resistance
• O2 heater element resistance is high
• Internal short or open in the heater element

Possible Symptoms:

O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 2

Possible Solutions:

• Replace oxygen sensor (cannot repair open or short that occurs internally to sensor)
• Repair short or open or high resistance in wiring harness or harness connectors

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2
– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit fuse
– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit open shorted to ground
– Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit poor electrical connection
– Faulty Engine Control Module (ECM)

Specific Makes:

– Possible higher than usual fuel Consumption