Technical Definition:

O2 Heater Circuit (Bank 2, Sensor 2)

Technical Description:

It basically means the PCM detected either an excessive current draw, or an open or short in the circuit powering the oxygen sensor’s heater circuit. This is in reference to the Heated Oxygen Sensor (2) located rear of catalytic converter (Bank 2).

Possible Causes:

• HO2S heater power circuit open
• HO2S heater ground circuit open
• HO2S signal tracking (due to oil or moisture in the connector)
• HO2S is damaged or has failed PCM has failed

Possible Symptoms:

HO2S Heater Performance Bank 2 Sensor 2

Possible Solutions:

• Replace HO2 Sensor
• Repair open or short in power circuit
• Repair open or short in ground circuit
• Repair damaged connector due to tracking

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Faulty Rear Heated Oxygen Sensor Bank 2
– Rear Heated Oxygen Sensor Bank 2 harness is open or shorted
– Rear Heated Oxygen Sensor Bank 2 circuit poor electrical connection
– Inappropriate fuel pressure
– Faulty fuel injectors
– Intake air leaks
– Exhaust gas leaks

Specific Makes:

– Possible higher than usual fuel consumption