P3012moderate severityPowertrain
Camshaft Profile Actuator B Stuck Bank 1
on 2021 Mazda Mazda3 2.5L I4 · FWD
What this code means
The camshaft profile switching actuator for Bank 1, exhaust side, is mechanically stuck. The exhaust cam profile affects scavenging and emissions.
Symptoms
- Check Engine Light
- Poor emissions performance
- Reduced engine braking
- Slight power loss
- Failed emissions test
Common causes
- Oil sludge in actuator passages
- Faulty solenoid
- Low oil pressure to actuator
- Worn actuator mechanism
- Carbon deposits
Diagnostic steps
- Check oil condition and level
- Command exhaust cam profile switch
- Monitor cam profile position PID
- Test oil pressure at actuator
- Inspect actuator for carbon buildup
Repair notes
Replace exhaust cam profile actuator. Perform engine oil flush if sludge is present.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1