To fix issues with the onboard charger in the 2014 Nissan Leaf, follow these steps:

 
Identify the Problem
 

• • Ensure that the problem originates from the onboard charger by checking if the car isn't charging at public or home stations.
  • Verify if there are error messages on the dashboard or in the Leaf Spy app, which many owners use for diagnostics.
  • Check for any recent software updates from Nissan that might address charging issues.

 
Check the Charging Cable and Port
 

• • Inspect the charging cable for visible damage or wear. A faulty cable can mimic onboard charger issues.
  • Examine the charging port on the vehicle for dirt or debris that might prevent a proper connection.
  • Test charging with a different, known-to-be-working charging cable if possible.

 
Reset the Onboard Charging System
 

• • Sometimes a simple reset can solve charging problems. To reset the system, turn off the vehicle and disconnect the 12V battery for a few minutes.
  • Reconnect the battery, start the vehicle, and check if the issue persists.

 
Review Charging Station Compatibility
 

• • Check if the charging station you are using is compatible with the 2014 Nissan Leaf and supports the current you are trying to use.
  • Ensure you are using a station that the Leaf supports, especially when using Level 2 chargers.

 
Inspect the Onboard Charger Components
 

• • If you have mechanical skills, inspect the onboard charger's physical connections and components. Look for loose connections or corrosion.
  • If you are not comfortable doing this yourself, seek professional help from a certified Nissan technician.

 
Consult with a Professional Technician
 

• • If the problem persists after trying the above steps, it’s best to consult a professional who has experience with electric vehicles.
  • Request a diagnostic test from a Nissan service center to identify any deeper issues not visible to the owner.

 
Consider Warranty or Recall Repairs
 

• • Check if your vehicle is still under warranty or if there are any recalls related to the onboard charger for the 2014 Nissan Leaf.
  • If applicable, have Nissan carry out the repairs or replacements under warranty or recall policy.

By following these steps, you should be able to diagnose and possibly fix issues with the onboard charger. If the problem continues, professional assistance is recommended.