The Fluke 117 is a compact, CAT III 600‑V true‑RMS digital multimeter designed for electricians and field technicians, featuring an integrated non‑contact voltage detector and AutoVolt/Lo function to guard against ghost voltage. Common failure points on this model include dead or weak batteries, damaged internal display backlight, cracked front panel connectors, and worn or corroded input jacks that can cause intermittent measurement errors or false readings. First‑check diagnostics: verify the battery pack is fully charged and properly seated; inspect the front‑panel connector pins for corrosion or physical damage; confirm the AutoVolt/Lo function toggles correctly by testing a known AC source to rule out ghost voltage detection issues.[oss-gpt-20b]