The Elektronikon 1900‑0700‑05 is a low‑range regulator/air‑compressor controller panel used on Atlas Copco compressors. Common failure modes include power supply or relay board faults, display or keypad malfunction, and loss of communication with the compressor due to wiring or firmware issues; repair shops often report that after component replacement the unit still requires re‑programming by an Atlas Copco service technician. Begin troubleshooting by verifying 24 VAC input voltage and ensuring all terminal connections are secure, then check the status LEDs and error codes on the panel, followed by a visual inspection of relays, capacitors, and solder joints for signs of damage or overheating.[oss-gpt-20b]