Heidelberg Press M4.144.2009 Inverter is a high‑current power module used to supply the drive electronics of an offset printing press. Common failures on this board include burnt IGBTs or MOSFETs, damaged gate drivers, and overheating of the integrated heat sink due to poor airflow or clogged cooling fans; these often manifest as sudden loss of motor output or over‑temperature shutdowns. For units where specific fault data is unavailable, check for typical issues in industrial inverter circuits: verify that the DC link voltage is within spec, inspect the gate driver ICs and MOSFET arrays for discoloration or cracking, and confirm that the heat sink fins are clean and properly mounted. First‑check diagnostics should include a power supply verification (input AC, output DC), visual inspection of component integrity, and review of any error codes logged in the press controller’s diagnostic log.[oss-gpt-20b]