Problem: JSON encoding issue

I am getting an error after JSON encoding, mentioned below:
Missing close test="Art貥s coronaires irr駵li貥s avec subocclusion d\u2019une deuxi譥 septale de petit\n ^ in at line number 1 at column number 112"

This may not necessarily be Yii issue. Use an online tool of your choice like https://jsonlint.com/ to confirm your data is structured correctly. If you think it is a Yii issue then provide some more context to help someone understand the exact problem you are facing.