dual tds meter not working

[RealReef7]

I have a hm digitial dual tds meter, it quit working.. any ideas? The battery looks like its soldered with 2 wires. http://www.tdsmeter.com/products/dm1.html

 

[Bob Nell]

Mine looks similar. The wire plug comes out Mine is Velcroed to the RO and the back unscrewed to access 2 batteries