The JLG Curtis 17400700 Joystick Controller is a handheld input device used on aerial work platforms to transmit operator commands and emergency stops to the machine’s control system. Common failure modes for this model include worn mechanical switches, degraded printed‑board traces from vibration or moisture ingress, and loss of communication with the host controller due to faulty serial/USB connectors. Initial troubleshooting should verify that the joystick powers up (check 12 V supply and indicator LEDs), inspect all button contacts for continuity and physical wear, and confirm that the serial interface is transmitting proper data packets to the platform’s control unit. If those checks pass, review any error logs from the host controller for communication timeouts or checksum errors.[oss-gpt-20b]