Member Avatar for marnett14

I brought my Presario 2500 to Africa with me where my wife and I are doing some work. It sat for a few weeks, while we were getting things settled. I tried to turn it on and the screen will not turn on at all. I tried replacing the CMOS battery, but accidently broke the holder for the CMOS battery. When I turn on the computer all the lights come on as well as the cd rom. I don't know what else to try. The CMOS is not currently attached. Can a computer screen run with out that battery? What might the problem be, knowing that the problem started before the CMOS battery was accidently removed?

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Following 's external-monitor suggestion and noting 's report that no external image appeared, the fault narrows to either the laptop's video output/motherboard or the display subsystem (backlight/inverter/LVDS cable/T-CON). The CMOS cell only stores BIOS settings and clock; operation without it is normally possible, so a missing CMOS battery rarely by itself causes a totally blank screen (CMOS battery).

Common diagnostic checks and what they indicate:

  1. Flashlight test in a dark room. A faint image visible at an angle means the LCD is showing video but the backlight (inverter or CCFL) is dead. No faint image keeps the problem on the data side (LVDS cable, T-CON, GPU/mobo).

  2. External-display verification. Confirm the external port and the LCD/external toggle key were used. If an external monitor also shows nothing, the laptop is probably not producing video (BIOS/POST or GPU/motherboard level).

  3. POST/beep and LED patterns. Listen for beeps or watch keyboard LEDs for blink codes. Forcing a POST error by removing a RAM module can produce diagnostic beeps if an internal speaker is present.

  4. Reseat and power-reset sequence. With AC and battery removed, hold the power button 20-30 seconds, then reseat RAM and the screen LVDS connector at the hinge. Reconnect and power up.

  5. Inspect the broken CMOS holder only for exposed metal or shorting debris. A short could damage nearby traces; insulating exposed contacts and replacing the holder is prudent.

Safety and next steps: inverter and CCFL circuits carry high voltage — avoid probing live. If the flashlight test shows a faint image, replacing the inverter or backlight assembly is the next low-cost step. If both internal and external displays remain blank after the above checks, board-level diagnosis or replacement is likely required; local repair shops can bench-test the video circuitry.

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Member Avatar for Xlphos

Maybe the screen has gone. Can you get hold of a VGA cable to connect your laptop to a monitor?
Even if the screen is gone the rest of the laptop may work fine; at least this way you can test to see if anything else is wrong.

Member Avatar for marnett14

I have tried this, but have been unsuccessful in getting any image.

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