P05D9
PCV Regulator Valve Control Circuit Low
Generic OBD-II
Common symptoms
What you'll notice
- Check the PCV valve for any blockages or clogs and clean or replace if necessary.
- Inspect the PCV valve circuit wiring for any damage, loose connections, or corrosion and repair or replace as needed.
- Test the power supply to the PCV valve control circuit using a multimeter and replace any faulty components or connectors.
- Consult the vehicle or motorcycle manufacturer's service manual for any specific troubleshooting steps or recommendations for this particular error code.
Common causes
Most likely first
- Faulty PCV regulator valve
- Loose or damaged electrical connections to the PCV regulator valve
- Clogged or blocked PCV system
- Malfunctioning engine control module (ECM)
- Vacuum leak in the PCV system
How to diagnose & fix
Work through it in order
- Engine misfires or runs rough
- Poor fuel economy
- Difficulty starting the vehicle
- Stalling or hesitation while driving
- Illuminated check engine light
Read & clear P05D9 yourself
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