I have witnessed this problem several times and know that it can be a bit annoying when it turns off and on.
In order to turn the backlight ON and OFF, you must press both the following keys at the same time: Fn and ESC
When you do that, it will toggle the backlight off and on.
I look forward to hearing your feedback concerning whether or not your problem is fixed.
I hope to hear back that all is working. If this is so, please do not forget to rate my help on the top of this page (choose the number of stars and click the Submit button). If it is not, please respond below.
I will be standing by,Jason
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