Troubleshooting Tools 79Troubleshooting ToolsPower LightsCAUTION: Before you begin any of the procedures in this section, follow thesafety instructions in the Product Information Guide.The power button light (bi-color LED) located on the front of the computerilluminates and blinks or remains solid to indicate different states:• If the power light is off, the computer is either turned off or is notreceiving power.– Reseat the power cable in the power connector on the back of thecomputer and the electrical outlet.– If the computer is plugged into a power strip, ensure that the powerstrip is plugged into an electrical outlet and that the power strip isturned on. Also, bypass power protection devices, power strips, andpower extension cables to verify that the computer turns on properly.– Ensure that the electrical outlet is working by testing it with anotherdevice, such as a lamp.• If the power light is steady blue and the computer is not responding:– Ensure that the display is connected and powered on.– If the display is connected and powered on, see "Power Lights" onpage 79.• If the power light is blinking blue, the computer is in standby mode. Pressa key on the keyboard, move the mouse, or press the power button toresume normal operation. If the power light is blue and the computer isnot responding:– Ensure the display is connected and powered on.– If the display is connected and powered on, see "Power Lights" onpage 79.