Idle Air Control Solenoid Circuit Intermittent
2014-2021 Mazda Mazda6 2.5L I4
Description
The PCM has detected an intermittent electrical fault in the Idle Air Control solenoid circuit. The IAC solenoid connection is making and breaking contact, causing erratic idle speed behavior.
Symptoms
- Check Engine Light
- Erratic idle speed
- Idle fluctuates up and down
- Intermittent stalling
Common Causes
- Loose IAC solenoid connector
- Corroded IAC wiring or pins
- IAC solenoid with intermittent coil fault
- Damaged wiring near engine vibrating loose
- PCM connector issue
Diagnostic Steps
- Wiggle test IAC connector while monitoring idle speed
- Inspect IAC solenoid connector for corrosion or loose pins
- Test IAC solenoid resistance at various temperatures
- Check wiring for chafing or intermittent breaks
- Monitor IAC duty cycle for erratic changes
Repair Notes
Repair the IAC connector or wiring; replace the IAC solenoid if it has an intermittent internal fault.
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
P1504 on Other Vehicles
Common Questions
What does code P1504 mean on a 2014-2021 Mazda Mazda6?
P1504 stands for "Idle Air Control Solenoid Circuit Intermittent". The PCM has detected an intermittent electrical fault in the Idle Air Control solenoid circuit. The IAC solenoid connection is making and breaking contact, causing erratic idle speed behavior.
What are the symptoms of P1504 on a Mazda Mazda6?
Common symptoms of P1504 include: Check Engine Light, Erratic idle speed, Idle fluctuates up and down, Intermittent stalling.
What causes P1504 on a 2014-2021 Mazda Mazda6?
Common causes of P1504 include: Loose IAC solenoid connector, Corroded IAC wiring or pins, IAC solenoid with intermittent coil fault, Damaged wiring near engine vibrating loose, PCM connector issue.