48 
Boot Up and Initialization Troubleshooting
Instrument Boot Up Process
Typical instrument boot-up process flow
1. Plug in the AC power cord from a known good AC power source into the 
rear panel of the analyzer.
2. The yellow standby LED illuminates on the analyzer front panel to the 
left-hand side of the On/Off button. If the yellow Standby LED is not 
illuminating refer to the “Yellow Standby LED Does Not Illuminate” section 
in this chapter.
3. To turn the analyzer on, press the On/Off button. The yellow Standby LED 
should turn off and the green Power On LED should illuminate. A green 
Power On LED indicates that the power supply has received an “On” 
command from the A4 CPU assembly. If the green Power On LED is not 
illuminating refer to the “Green Power On LED Does Not Illuminate” 
section in this chapter.
NOTE If the analyzer AC power source was removed by the operator by pulling the 
power cord or by turning off the analyzer via a power main switch on a test 
rack, the analyzer will automatically power on without having to press the 
On/Off button on the front panel.