Is there something wrong with my TX1?

The red light shown on the image https://pasteboard.co/VyZ65DOq.png turn on, once I plug-in the ac-adapter. Is there something wrong with my TX1? I think this light is supposed to be off when the ac-adapter was plugged-in.

Is it CR5? If so, it indicates the power is active on the module.

Oh! How silly I am! Many thanks!