Dell OptiPlex 760 Service Manual - Page 161

Back to Contents Page Troubleshooting Dell™ OptiPlex™ 760 Service Manual Tools Dell Diagnostics Solving Problems Dell Technical Update Service WARNING: Before working inside your computer, read the safety information that shipped with your computer. For additional safety best practices information, see the Regulatory Compliance Homepage on www.dell.com at www.dell.com/regulatory_compliance. WARNING: Always unplug your computer from the electrical outlet before opening the cover. Tools Power Lights The power button light located on the front of the computer illuminates and blinks or remains solid to indicate different states: l If the power light is green and the computer is not responding, see Diagnostic Lights. l If the power light is blinking green, the computer is in standby mode. Press a key on the keyboard, move the mouse, or press the power button to resume normal operation. l If the power light is off, the computer is either turned off or is not receiving power. ¡ Reseat the power cable into both the power connector on the back of the computer and the electrical outlet. ¡ If the computer is plugged into a power strip, ensure that the power strip is plugged into an electrical outlet and that the power strip is turned on. ¡ Bypass power protection devices, power strips, and power extension cables to verify that the computer turns on properly. ¡ Ensure that the electrical outlet is working by testing it with another device, such as a lamp. ¡ Ensure that the main power cable and front panel cable are securely connected to the system board. See the following: ¡ Mini Tower - System Board Components ¡ Desktop - System Board Components ¡ Small Form Factor - System Board Components ¡ Ultra Small Form Factor - System Board Components l If the power light is blinking amber, the computer is receiving electrical power, but an internal power problem may exist. ¡ Ensure that the voltage selection switch is set to match the AC power at your location, if applicable. ¡ Ensure that the processor power cable is securely connected to the system board. See the following: ¡ Mini Tower - System Board Components ¡ Desktop - System Board Components ¡ Small Form Factor - System Board Components ¡ Ultra Small Form Factor - System Board Components l If the power light is steady amber, a device may be malfunctioning or incorrectly installed. ¡ Remove and then reinstall the memory modules (see Memory). ¡ Remove and then reinstall any cards. See the following: ¡ Mini Tower - Cards ¡ Desktop - Cards ¡ Small Form Factor - Cards l Eliminate interference. Some possible causes of interference are: ¡ Power, keyboard, and mouse extension cables ¡ Too many devices on a power strip ¡ Multiple power strips connected to the same electrical outlet Diagnostic Lights