P0056
HO2S Heater Control Circuit Bank 2 Sensor 2
2016-2016 Cadillac ATS 2.5L I4
Low SeverityPowertrainGeneric (SAE)
The 2016 Cadillac ATS is equipped with a 2.5L inline-4 engine. Below you'll find detailed p0056 diagnostic code information including labor time estimates, cost ranges, and technician notes specific to this engine configuration.
Description
Malfunction in the heater circuit for the downstream O2 sensor on Bank 2.
Symptoms
- Check Engine Light
- Failed emissions
- Poor catalyst monitoring
Common Causes
- Faulty sensor heater
- Blown fuse
- Wiring issue
Diagnostic Steps
- Check fuse
- Test heater resistance
- Inspect wiring
Repair Notes
Replace O2 sensor or repair wiring.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P0056 on Other Vehicles
Common Questions
What does code P0056 mean on a 2016-2016 Cadillac ATS?
P0056 stands for "HO2S Heater Control Circuit Bank 2 Sensor 2". Malfunction in the heater circuit for the downstream O2 sensor on Bank 2.
What are the symptoms of P0056 on a Cadillac ATS?
Common symptoms of P0056 include: Check Engine Light, Failed emissions, Poor catalyst monitoring.
What causes P0056 on a 2016-2016 Cadillac ATS?
Common causes of P0056 include: Faulty sensor heater, Blown fuse, Wiring issue.
Last updated: March 2026