Fixing 400 AMP Single-Card Welding Machine: No Output Issuebr Is your 400 AMP Single-Card Welding Machine failing to produce output? Don’t worry! In this video, we’ll diagnose and repair the no-output issue step by step. From checking the IGBT module and control card to troubleshooting the power supply, we cover it all. Whether you're a DIY enthusiast or a professional, these tips and tricks will help you restore your machine to optimal performance.