MacBook LCD Replacement
MacBook screen has 5 key components to it and any of these components can be damaged after an incident, this will determine wether if you need:
Here is the break down:
LCD
This is the front glass/panel part you can touch. If you have a cracked LCD, or lines on the screen or sometimes even black screen due to a crack, this is the part that gets replaced. Sometimes the crack feels like its under, but its actually this layer that is damaged which has a film over it that sometimes you cannot physically feel the cracked glass. If you have any lines on the LCD or colourful / rainbow parts, this is the layer that is damaged. This layer shows the image/data and the backlight combo behind it brightens it up and you can see the image.
Backlight LED
This is where the backlight is sending brightness (usually from the bottom of the screen or from behind all the backlight sheets), in some instances where there is liquid damage on the screen, these backlight LEDs die. If you have any issues with the backlight LEDs, entire display assembly replacement may be needed. (In most models)
Backlight Sheets
There are a number of sheets behind the LCD layer that reflect the brightness from Backlight LEDs equally around and behind the LCD layer, and the mixture of the 3 gives you the image you see. Sometimes the crack of the LCD can damage these very sensitive backlight sheets behind them. If you have issues with the backlight sheets, entire display assembly may be needed to be replaced unless you are okay with minor backlight sheet issues such as tiny brighter or darker spots after a new LCD is put on. Most clients are okay with minor issues with the backlight sheets, but if you do precise photo editing, I usually recommend people to go with complete display assembly replacement if applicable. (Please note that in most cases LCD replacement alone is good enough)
Camera Module
The camera module is usually placed on the top of the LCD and its cable is usually laying behind all the layers mentioned above, against the back of the casing. If you have a camera issue that is coming from the module behind the LCD, then usually its not worth going forward with screen replacement, especially since the new OSs allow you to use your iPhone/external webcam as secondary camera. Basically an LCD cannot be removed without being cracked in many cases, since its glued in to the casing and it often breaks more when its being removed by technicians. If you have any camera issues that is coming from the Display side and not from logic-board, then entire display assembly needs replacement in many cases. Also in most newer models, the camera holds important serial number and information to be paired with your logic-board. This means if camera or display assembly is replaced, it may bring some limitations in using the device afterwards. Some of these limitations could be, "True Tone" feature or "ALS" error when doing a hardware test. In some models such as A2442 or the 14" M1 or M2 or M3, the only way to fix your cracked screen is to keep these modules in place, so camera, backlight and original IC chips from the original screen need to be transferred in to the new casing. It has become very hard to fix some of the newer models, but the community always ends up winning and figuring it out, however it comes at a cost.
Casing
This is the metal part that holds everything together. If you have dents on this in a way that it cannot be fixed, then it may need replacement. The casings I sell are sometimes 3rd party or used original, or refurbished. The casing really doesn't make that much of a difference on how the computer performs, however the hinges are also part of this casing. If you have a broken hinge, the entire display assembly with its casing may need replacement in most models.
OPTION 1
Pros
In most cases, this is the cheaper option (except some models that require transferring of the IC chips), You get to keep your original casing and backlight sheets and camera. In some of the cases such as A2442 model, this is the ONLY option since entire display assembly replacement without limitations is not possible at this time.
Cons
Longer turnaround time of repair, minor backlight sheet damages/brighter or darker spots on the image, especially where the original impact was or where the cracks have opened up or on the edges where LCD is pushed back against the backlight sheets or stuck to it. If there are dents on the display assembly shelling, this may not be a good option.
OPTION 2
Pros
Quicker turnaround time of repair if the assembly is in stock, a very good option if you have excessive damage on your original casing, sometimes this may be the only option.
Cons
More expensive in some cases, in some models the "True Tone" functionality is limited, in some cases sleep function may be altered, and frame rate per second may be altered in some of the models. The colour of casing may change based on what our suppliers have in stock. For example if you have Rose Gold colour, and suppliers only have Space Grey or more commonly used colours, then you will have a multi coloured MacBook. (looks cool and unique in some cases, sometimes we dont have a choice)
Examples of Broken Screen
Horizontal or Vertical Lines
Half of Screen Black
Black Screen
Water Inside the Screen
Rainbow Coloured Lines