Atlas Copco Elektronikon 190007104 is a digital panel controller used on compressor systems, providing touch‑based user interface and remote control of motor drives and safety functions. Common failure modes for this class include loss of display or menu navigation due to capacitor degradation, power supply voltage drops causing the unit to reset or shut down, and firmware corruption that results in error codes such as “E01” or “E02”. First‑check diagnostics: verify 24 VAC input is within spec with a multimeter; inspect all connectors for corrosion or loose contacts; review any displayed error codes against the service manual, then test the controller’s internal diagnostic LEDs and reset function.[oss-gpt-20b]