Technical Definition:

O2 Heater Circuit (Bank 1, Sensor 1)

Technical Description:

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

Possible Causes:

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

Possible Symptoms:

O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1

Possible Solutions:

• Repair short or open or high resistance in wiring harness or harness connectors
• Replace oxygen sensor

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

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

Specific Makes:

– Possible higher than usual fuel Consumption