According to this failure, low voltage power supply may be faulty judgment. Low voltage transformer no +5 v, +15 V, +6.4 V voltage output. Computer control panel CPU get +5 v supply, resulting in a microwave oven without any reaction was no reason for the state of failure: (1) low-voltage transformer primary winding E is burning or open. Power block with a multimeter to measure the primary winding (normal resistance of 760Ω). Secondary winding, two secondary terminals (normal resistance of 5.5Ω); three-terminal secondary, intermediate terminals on both sides of the terminal are 2.4Ω, normal resistance between terminals on both sides of 4.8Ω. Otherwise transformer damage. (2) TO1 damaged power plug (use a knife to scrape the dirt can make good contact with the contacts); outlet copper cracking. Poor contact (with a screwdriver so that the two copper copper extrusion can be fastened, elastic fit); power cores off (no electricity), replaced with new lines.4aiservice manual download site