Technical data

Troubleshooting Guide 5
N1911A/1912A P-Series Power Meters 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)