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Tiago199988 (talk | contribs) (Created a guide on how to repair iPhone 6S with no image) |
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{{Repair Guide | {{Repair Guide | ||
|Device=IPhone | |Device=IPhone 6S | ||
|Affects parts=Motherboard | |Affects parts=Motherboard | ||
|Needs equipment=Soldering Iron, Hot-Air Station, Microscope | |Needs equipment=Soldering Iron, Hot-Air Station, Microscope | ||
| Line 13: | Line 13: | ||
--> | --> | ||
The | The Device turns on but it has no image. | ||
== Symptoms == | == Symptoms == | ||
<!-- | <!-- | ||
Detail all measurable or observable symptoms in this section. | Detail all measurable or observable symptoms in this section. | ||
--> | --> | ||
* Device | * Device boots but no image is displayed | ||
== Solution == | == Solution == | ||
| Line 29: | Line 26: | ||
--> | --> | ||
The no image problem can have 2 causes a bad display or a motherboard problem. | |||
=== Diagnostic Steps === | === Diagnostic Steps === | ||
The first | The first thing to do is to always rule out bad parts, so first try a new display on the phone if it works great all that is need is a screen replacement. | ||
If even with a new display the phone is unable to display any image the problem is on the motherboard. | |||
Start by inspecting the FPC connector for any liquid or physical damage. | |||
[[File:Iphone 6s lcd fpc.jpg|center|thumb|iPhone 6S LCD FPC]] | |||
If everything is fine take diode readings of the display FPC and compare them with the image bellow. | |||
[[File:PlaceHolder image.png|center|thumb]] | |||
If the diode readings you took are ok next thing to check is if the voltages need to display image are present. | |||
* PP5V7_LCM_AVDDH_CONN | |||
* PN5V7_LCM_MESON_AVDDN_CONN | |||
* PP1V8_LCM_CONN | |||
* PP5V7_MESON_AVDDH_CONN | |||
These voltages can be measured here and only show up with the device turned on. | |||
[[File:IPhone 6S Display Voltages.jpg|center|thumb]] | |||
It is common to have a short circuit on one of these lines, most of these lines also have a filter that acts kinda like a fuse and may open if there is overcurrent. | |||
If the voltages are present, the issue is likely on the MIPI lines. Most of these lines go straight to the CPU through a filter. If every filter is present and testing good, the fault is most likely within the CPU itself. | |||
Here is a Block diagram of how the picture circuit works. | |||
[[File:IPhone 6S Display Block Diagram.png|center|thumb|600x600px]] | |||
== Repair Steps == | |||
If by replacing by trying a new display the image fault is solved all you have to do its to replace the display. | |||
If there is a any physical damage to the FPC the solution is to replace it. The best method is to use a hot air station to desolder the old FPC, clean the old solder from the motherboard, apply new solder, align the new FPC, and use the hot air station to solder it. Be careful not to use excessive heat, as you may cause a solder bridge under the motherboard. | |||
When taking diode readings of the FPC, if you measure a line that should read, for example, 0.500V but get 0.100V or 0.000V, it indicates a short on that line. The best way to trace the short is to inject voltage into the line with a DCPS and use a thermal camera to identify which component heats up. Fallow this guide how to find the short [[Short Circuits - Repair Basics]] | |||
If you measure a line that should read 0.500V but get OL (Open Line), it indicates a disconnection in the circuit. To trace the issue, consult the board view to follow the line’s path. | |||
If you have to replace a Filter the best way is to use your hot air station with a low air speed or the component may fly away. | |||
If any of the voltages are missing, use the block diagram to trace where the voltage is generated and replace the chip responsible for creating that voltage. These components are easily available online and are generally easy to find. | |||
== Final Testing == | |||
After assembling the phone, ensure every function is working as expected, not just the display, there are a lot of small components around the LCD FPC and when heating this area sometimes you end up desoldering something by mistake. | |||
Latest revision as of 23:42, 2 December 2025
| IPhone 6S No Image | |
|---|---|
| Device | IPhone 6S |
| Affects part(s) | Motherboard |
| Needs equipment | Soldering Iron, Hot-Air Station, Microscope |
| Difficulty | ◉◉◉◌ Hard |
| Type | Soldering |
This article is a stub. You can help Repair Wiki grow by expanding it
Problem description
The Device turns on but it has no image.
Symptoms
- Device boots but no image is displayed
Solution
The no image problem can have 2 causes a bad display or a motherboard problem.
Diagnostic Steps
The first thing to do is to always rule out bad parts, so first try a new display on the phone if it works great all that is need is a screen replacement.
If even with a new display the phone is unable to display any image the problem is on the motherboard.
Start by inspecting the FPC connector for any liquid or physical damage.
If everything is fine take diode readings of the display FPC and compare them with the image bellow.
If the diode readings you took are ok next thing to check is if the voltages need to display image are present.
- PP5V7_LCM_AVDDH_CONN
- PN5V7_LCM_MESON_AVDDN_CONN
- PP1V8_LCM_CONN
- PP5V7_MESON_AVDDH_CONN
These voltages can be measured here and only show up with the device turned on.
It is common to have a short circuit on one of these lines, most of these lines also have a filter that acts kinda like a fuse and may open if there is overcurrent.
If the voltages are present, the issue is likely on the MIPI lines. Most of these lines go straight to the CPU through a filter. If every filter is present and testing good, the fault is most likely within the CPU itself.
Here is a Block diagram of how the picture circuit works.
Repair Steps
If by replacing by trying a new display the image fault is solved all you have to do its to replace the display.
If there is a any physical damage to the FPC the solution is to replace it. The best method is to use a hot air station to desolder the old FPC, clean the old solder from the motherboard, apply new solder, align the new FPC, and use the hot air station to solder it. Be careful not to use excessive heat, as you may cause a solder bridge under the motherboard.
When taking diode readings of the FPC, if you measure a line that should read, for example, 0.500V but get 0.100V or 0.000V, it indicates a short on that line. The best way to trace the short is to inject voltage into the line with a DCPS and use a thermal camera to identify which component heats up. Fallow this guide how to find the short Short Circuits - Repair Basics
If you measure a line that should read 0.500V but get OL (Open Line), it indicates a disconnection in the circuit. To trace the issue, consult the board view to follow the line’s path.
If you have to replace a Filter the best way is to use your hot air station with a low air speed or the component may fly away.
If any of the voltages are missing, use the block diagram to trace where the voltage is generated and replace the chip responsible for creating that voltage. These components are easily available online and are generally easy to find.
Final Testing
After assembling the phone, ensure every function is working as expected, not just the display, there are a lot of small components around the LCD FPC and when heating this area sometimes you end up desoldering something by mistake.