Troubleshooting Guide
4
Keysight N1911A/1912A Service Guide
51
Power-Up Problems
Basic external checks
– Check the mains power source is live
– Check the mains fuse is operational
– Check the mains cable for any obvious damage
– Check the line module fuse in the instrument is operational
Basic internal checks
– Check/reseat the cable between the line module and the PSU
– Check/reseat the cable between the PSU and the main board
– Green LED DS1: If this is off, then the PSU may be faulty
– Green LED DS4: This should come on when the power button is pressed
– Green LEDs DS2/DS3: These will flash on and off during normal operation
Possible faults
– PSU
– Main board
– Front panel (defective keymat, key flex circuit, or display)
– Loose front panel cable (connection to main board)
