Replace Batteries in a Field Gauge LC20
- Power off the gauge.
- Remove the four screws from the back of the gauge with a 2mm hex key/Allen wrench or Phillips-head screwdriver. Older models shipped with hexagonal sockets, newer models ship with Phillips-head screws.
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- Remove the back panel.
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- Remove expired batteries, and replace with fresh AA batteries.
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- Be sure to properly align the positive and negative ends to the proper contacts.
- Replace the back panel.
- Insert and tighten the four back panel screws to 5 in-lb (0.6 N-m) to maintain water resistance.
- Power on the gauge to confirm the new batteries are charged and installed properly.