P04D1
EGR Temperature Sensor C Circuit High
Generic OBD-II
Common symptoms
What you'll notice
- Verify the EGR temperature sensor wiring connection for any loose or corroded terminals
- Inspect the EGR temperature sensor for any signs of damage, such as cracks or corrosion, and replace if necessary
- Clean the EGR system components, including the EGR temperature sensor, to remove any carbon buildup or debris
- Test the EGR temperature sensor using a multimeter to ensure it is functioning correctly, and replace if necessary
- If all else fails, consider replacing the EGR valve itself, as a malfunctioning valve could be causing the high circuit reading
Common causes
Most likely first
- Faulty EGR temperature sensor
- Short or open circuit in the wiring associated with the EGR temperature sensor
- Failed EGR valve
- Engine coolant temperature sensor malfunction
- ECM (engine control module) malfunction
How to diagnose & fix
Work through it in order
- Check engine light illuminates
- Decreased fuel efficiency
- Rough idling or engine misfire
- Engine stalling or hesitation
- Increased emissions
Read & clear P04D1 yourself
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