E-series RTC coin battery

As suggested in the e-series evaluation board manual, I attached a 3.3 v coin cell to the bottom of the board and toggled the DIP switch that connects VBAT to 3V3 to OFF. However the e-series unit RTC is not maintaining Time and when I check voltage at the VBAT pin on the header the voltage is essentially 0.
Shouldn’t the VBAT pin read the coin battery voltage? If not is there someplace else I can check to see if the coin cell is feeding the RTC?
john

Problem solved. The ground pad on the back side of the evaluation board did not make adequate contact with the neg. side of the battery. Placing a small piece of metal foil between the neg. side of the battery and the pad on the evaluation board solved the problem. When I next disassemble the unit I’ll add a small bump of solder to the ground pad so that it will push against the battery better. So just a heads-up, the coin battery pads/holder might need some fooling with to get good contact.

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