Compaq dx7400 Troubleshooting Guide - Page 61

Interpreting POST Diagnostic Front Panel LEDs and Audible Codes

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Interpreting POST Diagnostic Front Panel LEDs and Audible Codes This section covers the front panel LED codes as well as the audible codes that may occur before or during POST that do not necessarily have an error code or text message associated with them. WARNING! When the computer is plugged into an AC power source, voltage is always applied to the system board. To reduce the risk of personal injury from electrical shock and/or hot surfaces, be sure to disconnect the power cord from the wall outlet and allow the internal system components to cool before touching. NOTE: If you see flashing LEDs on a PS/2 keyboard, look for flashing LEDs on the front panel of the computer and refer to the following table to determine the front panel LED codes. Recommended actions in the following table are listed in the order in which they should be performed. Not all diagnostic lights and audible codes are available on all models. Activity Possible Cause Recommended Action Green Power LED On. Computer on. None Green Power LED flashes every one second. Processor thermal protection 1. Ensure that the computer air vents are not blocked activated: and the processor cooling fan is running. A fan may be blocked or not 2. Open hood, press power button, and see if the turning. processor fan spins. If the processor fan is not spinning, make sure the fan's cable is plugged onto OR the system board header. Ensure the fan is fully/ The heatsink/fan assembly is properly seated or installed. not properly attached to the WARNING! Rotating fan blades can cause processor. serious bodily harm. Be sure to keep your hands away from the rotating blades. 3. If fan is plugged in and seated properly, but is not spinning, then replace processor fan. 4. Reseat processor heatsink and verify that the fan assembly is properly attached. 5. Contact an authorized reseller or service provider. Green Power LED flashes twice per Computer in Suspend to RAM Press any key or move the mouse to wake the computer. second. mode or normal Suspend mode. Green Power LED flashes five times, once per second, followed by a short beep. Pre-video memory error. CAUTION: To avoid damage to the DIMMs or the system board, you must unplug the computer power cord before attempting to reseat, install, or remove a DIMM module. 1. Reseat DIMMs. 2. Replace DIMMs one at a time to isolate the faulty module. 3. Replace third-party memory with HP memory. 4. Replace the system board. Green Power LED flashes six Pre-video graphics error. times, once every second, followed by one long and two short beeps. For systems with a graphics card: 1. Reseat the graphics card. 2. Replace the graphics card. 3. Replace the system board. ENWW Interpreting POST Diagnostic Front Panel LEDs and Audible Codes 55

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Interpreting POST Diagnostic Front Panel LEDs and
Audible Codes
This section covers the front panel LED codes as well as the audible codes that may occur before or
during POST that do not necessarily have an error code or text message associated with them.
WARNING!
When the computer is plugged into an AC power source, voltage is always applied to the
system board. To reduce the risk of personal injury from electrical shock and/or hot surfaces, be sure
to disconnect the power cord from the wall outlet and allow the internal system components to cool
before touching.
NOTE:
If you see flashing LEDs on a PS/2 keyboard, look for flashing LEDs on the front panel of the
computer and refer to the following table to determine the front panel LED codes.
Recommended actions in the following table are listed in the order in which they should be performed.
Not all diagnostic lights and audible codes are available on all models.
Activity
Possible Cause
Recommended Action
Green Power LED On.
Computer on.
None
Green Power LED flashes every
one second.
Processor thermal protection
activated:
A fan may be blocked or not
turning.
OR
The heatsink/fan assembly is
not properly attached to the
processor.
1.
Ensure that the computer air vents are not blocked
and the processor cooling fan is running.
2.
Open hood, press power button, and see if the
processor fan spins. If the processor fan is not
spinning, make sure the fan's cable is plugged onto
the system board header. Ensure the fan is fully/
properly seated or installed.
WARNING!
Rotating fan blades can cause
serious bodily harm. Be sure to keep your hands
away from the rotating blades.
3.
If fan is plugged in and seated properly, but is not
spinning, then replace processor fan.
4.
Reseat processor heatsink and verify that the fan
assembly is properly attached.
5.
Contact an authorized reseller or service provider.
Green Power LED flashes twice per
second.
Computer in Suspend to RAM
mode or normal Suspend
mode.
Press any key or move the mouse to wake the computer.
Green Power LED flashes five
times, once per second, followed
by a short beep.
Pre-video memory error.
CAUTION:
To avoid damage to the DIMMs or the
system board, you must unplug the computer power cord
before attempting to reseat, install, or remove a DIMM
module.
1.
Reseat DIMMs.
2.
Replace DIMMs one at a time to isolate the faulty
module.
3.
Replace third-party memory with HP memory.
4.
Replace the system board.
Green Power LED flashes six
times, once every second, followed
by one long and two short beeps.
Pre-video graphics error.
For systems with a graphics card:
1.
Reseat the graphics card.
2.
Replace the graphics card.
3.
Replace the system board.
ENWW
Interpreting POST Diagnostic Front Panel LEDs and Audible Codes
55