To address the issues with the LED daytime running lights failing on certain Mazda CX-5 models, follow these steps:

 
Identify the Affected Model Years
 

• Determine if your Mazda CX-5 falls within the model years known for LED daytime running light issues. Typically, this issue has been reported in models produced between 2016 and 2018.

 
Check for Recall or Technical Service Bulletins (TSBs)
 

• Contact your local Mazda dealership or visit Mazda’s official website to check if there are any recalls or TSBs related to the daytime running lights for your vehicle's model year.

 
Inspect the LED Lights and Connections
 

• Inspect the LED running lights for any visible signs of damage or failure.
• Check the electrical connections to ensure they are secure and free of corrosion or damage.

 
Replace LED Bulbs
 

• If the bulbs themselves are the problem, you may need to replace them. Purchase LED replacement bulbs compatible with your Mazda CX-5 model year.

 
Consult a Professional Mechanic
 

• If the issue persists after replacing the bulbs, it’s advisable to consult a professional mechanic or an authorized Mazda service center for a detailed diagnosis and potential repair of the electrical system.

 
Consider Full Headlight Assembly Replacement
 

• In some cases, the issue might be with the entire headlight assembly. Replacing the entire unit could be necessary, particularly if there is a manufacturing defect.
• Check if this is covered under warranty or recall, as these assemblies can be expensive.

 
Preventive Measures
 

• Regularly check the functionality of your daytime running lights to catch any failures early.
• Keep the electrical connections clean and protected from moisture to prevent future issues.