Symptoms of a Loose or Disconnected Video Connector in a Laptopby Dan Stone
Laptop loose video connector symptoms can range from intermittent display irregularities to an entirely disabled screen. Laptop screens and motherboards are connected by a single cable within the system that runs through the pivot point that controls the screen orientation. The cable can get disconnected from either side from regular wear and tear use over time or be knocked out of position through impact.
The video cable might be loose if the laptop turns on correctly and only displays a bright white or gray screen with no video content. The blank screen will display like the lights are on, but nobody's home. The bright, blank screen implies that the monitor is getting power, but the video signal isn't coming through from the motherboard. If the laptop is able to display video on an external monitor, the internal cable may be loose.
No Backlight or Very Dim Screen
A loose monitor cable can cause the backlight to receive insufficient power and have the screen display a dim, almost impossible to see screen. If the screen doesn't light up at all, try shining a flashlight on the screen to see if there's an image. The cable may be loose if you can see a faint image on the screen with the aid of a bright light source. However, this phenomenon is also a symptom of a failed backlight.
No Signal or Power
A loose cable can cause the laptop's monitor not to turn on at all. The screen will not work at all if the cable is completely disconnected from either end. If the cable is loose enough, the backlight will not receive any power and the screen will not display any image. The problem can be resolved by reconnecting the cable, but a completely inactive screen is also a symptom of a broken screen.
Screen flicker is a loose cable symptom. The cable might be loose if the screen consistently flickers for a split second at a time. Screen flicker implies that the connection is loose and unable to maintain a constant connection with the computer. However, video flicker can also be caused by a low monitor refresh rate; the higher the refresh rate the less likely a viewer will notice screen flicker.
If the video drops in and out depending on the position of the screen, there is likely a loose video cable connection in the laptop. Moving the screen back and forth may wiggle the cable enough to make the difference between a complete and incomplete monitor connection. Additionally, moving the screen to a very far back position may pull on the connection cable a little more than positioning the screen in a perpendicular position and disrupt the display.