Keysight N9038A MXE Service Guide 57
Boot Up and Initialization
Potential Problems During Boot Process
Figure 2-9 A1A2 Front Panel Interface Board LCD Backlight Control Voltages
12.Are all of the 3 voltage levels within their expected ranges?
If yes:
Replace the A1A4 Display Backlight Power Supply.
If not:
Replace the A1A2 Front Panel Interface board.
Table 2-2 Expected Backlight Inverter Control Voltage Levels
Signal Expected Voltage
Brightness Control 0 to 3 VDC
Backlight Enable >6 VDC
Backlight Supply +12 VDC