ES&S TSI Printer motherboard is the main control board used in high‑volume thermal printers, integrating power regulation, firmware logic, and I/O interfaces to the print head and carriage drive. Common failure points on this class of boards include damaged voltage regulator ICs, cracked solder joints on the serial/USB connectors, and burnt capacitors that cause intermittent or total loss of communication with the printer chassis. First‑check diagnostics: verify 12 V/5 V supply rails with a multimeter; inspect all connectors for loose pins or corrosion; review any error codes displayed on the printer’s status panel or logs for patterns such as “COMM_FAIL” or “OVERHEAT.”[oss-gpt-20b]