New Fluke 113

[Techbox]

Hi = )

I have had several multimeters before but finally broke down and bought a Fluke 113. I have been messing with it trying to get used to it and understand it and there is something that is bothering me about it. I took a 3.2v coin cell battery out of a PC motherboard to measure it. I put the positive lead on the positive ( + ) battery side and the negative lead on the negative side and I get absolutely no read except open line. However, if I switch the positive lead and the negative lead around it reads correctly, anywhere from 2.6v to 3.2 volts depending on the age of the battery. Why is this??? ( and yes my negative lead is plugged into "com" and my positive lead is plugged into " +"

TIA