Brand: GE Model Number: SCB1001MSS01 Main Symptom: Controls and display not working intermittently What happens & when: At times the buttons don’t work and at times the display flickers or shows strange symbols. After resetting the microwave by turning power off and on, it will work correctly for about a week before the issue returns. This has been happening for over 6 months. Wondering which part needs to be replaced.
Error Code (if any): none
Parts or tests already tried: power off / on
Photos / video link: none
This could be caused by the Main PCB, the Relay PCB, the Power PCB, or even the low voltage transformer. Voltage testing when the user panel is failing would be necessary to identify which of these parts are the cause of failure. During failure, the Power PCB can be tested for DC voltage at connection CN7 from pin 5 to pin 4, pin 2 to pin 3, and pin 2 to pin 1 while the wires are connected. There should be 7 Volts DC, 19 Volts DC, and 12 Volts DC respectively if the low voltage transformer is ok. From there, the connection CN4 would need to be tested for DC voltage from pin 15 to pins 1 (5VDC), 2 (14VDC), 3 (7.5VDC), 4 (12VDC), 5 (0-5VDC), 6 (5VDC), 7 (0-5VDC), 8 (14.5VDC), 9 (4VDC), 10 (5VDC), 11 (4.7VDC), and 12 (5VDC). Then at connection CN11, it should measure 15 VDC from pin 1 to pin 2, and 12VDC from pin 1 to pin 3. If any of these voltages are missing, the Power PCB has failed. If these voltages are present, let me know and we can go into further testing. Here is a link where the power PCB can be viewed for reference. WB27X10861 Pcb Electronic Power Board | Genuine Ge OEM In Stock