no backlight on lcd panel 14 inc in stock

Got a free 27 LED Cinema Display with dark back light (BL) 99% of the time plugging in Display Port. Finally isolated a deterministic sequence that worked for a day. Wife has the same monitor and also not coming on 80% of time when plugging in Display Port. Here is the working sequence.

This sequence got the monitor up and working for a couple of hours but since then seem to have more difficulty and backlight just flickers now on the lowest sitting and shutoff at any higher settings. I guess there are thermal related weak solder points likely in the LED strip in the panel.

Plug in Cinema Macbook Magsafe connection (probably don’t need this but might as well get MB ready to close the clamshell later while Cinema Display remains on)

Use external keyboard (pair it in advance if wireless) F1 key. Click it many times to set external monitor brightness to lowest setting (even though you think its not on)

Click F2 1x (brighter), strobing probably go a little faster, wait 10s and see if it comes on permanently. if not, click F2 1x brighter and repeat until backlight stays on stable.

This is probably the common LED strip solder resistance problem. The backlight circuit compares the different LED channels for voltage. If difference too large, circuit shuts off. Had this in my 27” iMac (2009 so same LCD panel as the 27 LED Cinema Display) It would not go very bright before self shutting off backlight. I pulled apart the LCD panel and reflowed the LED connections and now works perfect. Tearing apart the panel to get to LED strip require handy skills and cautious approach. Very easy to damage and hard to keep dust+threads out of panel+diffuser layers during reassembly. Below is the full link on that.

Fixed 2 of these LCDs (2009 iMac 27”, Cinema LED Display 27”) Only need to apply nice leaded solder to the LED strip connectors. On my Cinema LED Display, one of the connectors just fell off the strip during disassembly. Was barely hanging on. Wasn’t just the 6 pin connection. Also the 2 connector anchor solder points. Must be really bad soldering during manufacturing.

Each connector has 6 lines so each line drives 6 LEDs (36 LED/strip). The connector solder joints is the highest thermal stressed solder joint in the circuit.

On the iMac, I also touched up every LED. I’m guessing this wasn’t necessary and the iMac color temperature is also a lot warmer. I’m guessing the heat from soldering iron affected the LEDs.

No brightness control (after swapping a failed panel with one with early failure symptoms (still lights up but not all the time unless mac brightness is set to low at connection time)

Max brightness is really dim (after swapping a failed panel with one with early failure symptoms (still lights up but not all the time unless mac brightness is set to low at connection time)

Newhaven 160x100 graphic Chip-On-Glass (COG) Liquid Crystal Display shows dark pixels on a gray background. This reflective LCD Display is visible with high ambient light while offering a wide operating temperature range from -20 to 70 degrees Celsius. This NHD-C160100CZ-RN-FBW display has an optimal view of 6:00 and has no backlight. This display operates at 3V supply voltage and is RoHS compliant.

Adjust the length, position, and pinout of your cables or add additional connectors. Get a cable solution that’s precisely designed to make your connections streamlined and secure.

Easily modify any connectors on your display to meet your application’s requirements. Our engineers are able to perform soldering for pin headers, boxed headers, right angle headers, and any other connectors your display may require.

Choose from a wide selection of interface options or talk to our experts to select the best one for your project. We can incorporate HDMI, USB, SPI, VGA and more into your display to achieve your design goals.

Choose from a wide selection of changes including shape, size, pinout, and component layout of your PCB to make it a perfect fit for your application.

This website is using a security service to protect itself from online attacks. The action you just performed triggered the security solution. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data.

Dell recommends ensuring that the device drivers and BIOS are up to date using the SupportAssist application for optimal video performance and to help resolve common video-related issues.

NOTE: When SupportAssist does not show up in the search results, go to the SupportAssist for PCs and tablets page for information about downloading and installing SupportAssist.

To learn how to manually download and install a device driver such as Chipset, Video card (GPU), and Monitor driver (if required, most monitor drivers are delivered automatically through Windows Update) on your Dell computer, see the Dell knowledge base article How to Download and Install Dell Drivers.

We must verify whether the problem is the display screen of the laptop, video card (GPU), or video settings on the computer. A straightforward way to identify this is to connect the laptop to an external monitor or TV.

If the issue persists on the external monitor, it may be an issue with the video card (GPU) or video settings and not the laptop LCD panel. Go to verify display or video issues in Windows Safe Mode. Otherwise, go to the next step.

Performance issues may occur if there is any damage to the LCD screen. The display may stop working, work intermittently, flicker, display horizontal or vertical lines, and so on, if there is damage to the display screen.

If you notice a physical damage, contact Dell Technical Support to learn more about repair options that are available in your region. If there is no damage, go to the next step.

Dell laptops have integrated diagnostic tools that can determine if the screen abnormality is an inherent problem with the LCD screen of the Dell laptop or with the video card (GPU) and computer settings.

When you notice screen abnormalities like flickering, distortion, clarity issues, fuzzy or blurry images, horizontal or vertical lines, color fade, running a diagnostic test on the LCD helps identify if the issue is with the LCD panel.

Press and hold the D key and turn on the computer to enter the LCD built-in self-test (BIST) mode. Continue to hold the D key until you see the entire screen change colors.

If you do not detect any screen abnormalities in the integrated self-test mode, the LCD panel of the laptop is functioning properly. Go to the Update the video card (GPU) driver, monitor driver, and BIOS section.

If you notice any abnormalities in the LCD built-in self-test mode, contact Dell Technical Support to learn more about repair options that are available in your region.

Windows Safe Mode does not load any drivers, startup applications, third-party services. This will help us identify if the issue is related to the operating system, video settings, device drivers, or third-party software. To learn how to boot your computer into Safe Mode, see the Dell knowledge base article below based on the operating system that is installed on the computer:

Windows updates can support your Windows operating system in many ways. Windows updates can solve specific problems, provide security patches and protection from malicious attacks, or even add new features to the operating system.

Display settings like brightness, refresh rate, resolution, and power management may affect the performance of the LCD screen on your Dell laptop. Changing or adjusting the display settings can help resolve several types of video issues.

NOTE: Depending on the model of the Dell laptop, the shortcut keys to adjust or change the brightness may differ. See the User Guide or User Manual of your Dell laptop for model-specific information.

If you find that the Dell laptop is unresponsive to touch, touch stops working entirely, or other touch-related issues, you can try some common troubleshooting steps to help fix the touch-related issue.

Stress Test can thoroughly diagnose the video card (GPU) on your computer and report any potential hardware problem. Running a stress test on your computer can verify if the hardware components are stable and thus reliable.

System Restore is an integrated Windows tool that is designed to protect and repair the operating system. When something goes wrong with your computer, System Restore must be used before you try to restore the operating system to factory default settings.

If the diagnostic tests on the LCD panel and the video card (GPU) passed, it is most definitely an issue that is related to software that is installed on the computer. If the above troubleshooting steps did not resolve the issue, you may try to restore the computer to factory default settings as a last resort.

WARNING: Restoring or resetting the computer to factory default settings will erase all personal data on the computer. Back up all important data like documents, images, music files, spreadsheets, videos to an external hard drive or a cloud-based backup like Microsoft OneDrive.

Dell computers are built with a small amount of hard disk space that is reserved for reinstalling the operating system. This method is the easiest way to restore the computer to factory condition. The restoration process deletes all user data from the computer, so be sure to back up all your files before starting this process.

Laptop screens may break or crack on occasion. The 14-inch screen size is widely used for laptops and notebooks. When you need to replace your screen for one reason or another, it"s important to know what types of 14-inch LED LCD laptop screens are available.

LED LCD monitors provide you with LCD technology that uses an LED backlight. The LCD or liquid crystal display consists of liquid between two layers of glass. The crystals are lit from the back with an LED to provide you with the light source.

The aspect ratio of a computer display expresses the screen size by means of the proportional relationship between its width and its height. This is typically expressed as two numbers with a colon between them. When you"re shopping for a laptop screen, the two common ratios to choose from are 16:10 and 16:9.

It"s important to review what type of LCD screen is compatible with your device. Whether it"s ASUS, Samsung, Dell, Toshiba, Acer, Lenovo, or another brand, you have to identify the specifications. You will need to know both the brand and the product line. This way, you can expect that the LCD screen will fit properly. See the manufacturer site for details.

Each LCD screen model may have a slightly different procedure, so refer to owner"s instructions. However, in general, to replace the screen, you will need to remove the bezel that surrounds it. Depending on the model of laptop you have, this may require a few different steps. Once the bezel is off, you can remove the broken screen. This will involve disconnecting one or two cables. You can then reverse the steps once you have the new screen in your hand. Once installed, you should test the screen to make sure everything is working properly.

When you shop for an LCD screen, there may be some features you want to have. You need to review the specifications of the laptop screen to make sure you get what"s needed for your individual application.

Ever had your TV showing nothing but a black screen even if the audio was working? Unfortunately, that’s a common issue with low/middle-end LCD/LED TVs these days… Even more frustrating, this issue often comes from a rather tiny and cheap component that can be easily replaced. Most common issues are:

One of my relatives had this exact symptom happening all of a sudden. This problem on low-end TVs often occurs within the first couple years. As the repair costs for that kind of TV is pretty low, considering repairing it yourself might be a good idea!

The first step into repair is to find the root cause of the issue. As backlight failure is a very common issue, this is the first thing to test. To do so, the easiest way is to power on your screen, put a flashlight very close to it and check if you can see the image through. The image would be very dark, like turning the brightness of the screen very very low.

That implies disassembling the TV to access the backlight which is between the LCD screen in the front and the boards in the rear. In my case, with a Samsung F5000, I had to process as follows:

First we have to remove the back housing to reveal the boards (from left to right: main board, T-CON, power supply) and disconnect the LCD panel from the T-CON board.

Note: Older TVs have neon tubes for backlight, which is thicker and less exposed to this kind of failure. LED backlight is the most common thing these days, but do not mistake an LED TV with an OLED TV. The first one is a classic LCD panel with a LED backlight, whereas the second is an OLED panel that doesn’t need any backlight as it is integrated in each pixels (making the spare parts much more expensive by the way).

As we can see, the backlight system is made of 5 LED strips. First thing to do is look for burnt LEDs. Most LED backlight systems have strips set in series, meaning that if one of the them fails, all the system goes dark…

Using a multimeter, we can confirm that the strips are indeed set in series, so now we have to test each strip individually. Professionals use LED testers such as this one (about 40$ on amazon) but as I didn’t had one at the time, I decided to make one, McGyver style!