Apple monitors the preferences of its users. And of course it tries to keep the bar between smartphone manufacturers.
The iPhone's many features are increasingly making the brand more ingrained among its fans. The appearance of a flashlight on the iPhone added positive feedback users. This feature is used much more often than one might initially imagine. An indispensable thing at night, as well as for people with visual impairments. And of course, an unexpected breakdown of the function in question is accompanied by all sorts of inconveniences.
Breakdowns happen for various reasons. This malfunction is more or less related to the camera or flash. The device fails when, for example, an overheating signal appears or the camera simply stops functioning, and when you try to use it, only a black screen is visible. Of course, taking the smartphone owner by surprise, the lack of flashlight light deprives us of a useful function. You can get help by contacting service center. Let's consider the reasons for the occurrence of breakdowns of this kind. The following descriptions also apply if the iPhone 4 flashlight or iPhone 5s flashlight does not work.
Reasons why the flashlight on an iPhone does not work
There are several reasons why the flashlight is not working:
1 For example, the device has been in water for a long time, as well as moisture penetration due to damage to the seal. 2 In case of mechanical damage to the device or a fall. 3 When more force was used when touching the camera icon than required by the rules of use. 4 If the installation of the flashlight application on your smartphone was completed with errors or it was not installed at all. 5 Unqualified implementation of the device by unwinding, reprogramming, and so on.
iPhone 4s flash not working
Let us highlight two points: mechanical damage, not correct installation application functions and water getting inside the device. You can solve the problem yourself using the following recommendations.
In the menu item there is a corresponding symbol, “flashlight”, which activates the flash, which acts as a flashlight. There is an LED hole on the back cover of the iPhone and the absence of signs of glow indicates its malfunction. You can analyze the subject of a breakdown by moving from one (faulty) camera to another. If it doesn't work, then the reason is in the camera circuit. Solve the problem of technical nature Reflashing will help. This method allows you to return the correct operation of the non-working flash on the iPhone 4s, with the help of which everything should turn on. Of course, you can do the reinstallation yourself, but at the risk of losing information.
If the flash does not work on the iPhone 5 or the flash does not work on the iPhone 5s, the same manipulations apply. Also, when the flash on the iPhone 6 does not work, you can use flashing the device.
Another way when, for example, the flash on the iPhone 5 does not work. You can try restarting the camera program. And if the camera does not start correctly right away, you can use Apple technical support.
There is another common problem of malfunctions of the camera and its connecting flash and flashlight. This is not a working device after the update.
Restoring iPhone flashlight functions after updating
- Perform the manipulation of turning on or off the power saving mode (you can turn it on with a voice command).
- Switch from one camera to another until the black screen disappears.
- Mechanically influence the camera icon, but do not overdo it.
- Disable or stop applications that use the camera.
Try to enable the feature being adjusted.
- We perform a hard reboot of the device.
- General reset of settings and content.
- We restore the device through the DFU mode.
If the flashlight on the iPhone 5 does not turn on, you can risk repairing the smartphone yourself. But remember, gadgets under warranty should not be touched and it is better to take advantage of the provided warranty. This service has been allocated for 2 years and if you have not untwisted your iPhone, the service center will fix the breakdowns.
Typically, the camera is equipped with a high-brightness flash, which can also serve as a flashlight. This is a very convenient and useful thing that works simply and without problems. How does it work and how can you turn on the flashlight on your mobile phone running Android? Naturally, this can be done in several ways: using standard functions of the Android operating system (widget), as well as downloading applications.
New OS Android 5.0+ allows you to activate the flashlight on your phone without installing third-party applications. To do this, you need to pull down the top curtain and also find the flashlight icon. In English versions it may be referred to as flashlight. This is the easiest way to turn on the flashlight on a phone that has a camera with flash.
Once the button is activated, the LED on the back of the phone will work, brightly illuminating the surrounding area. Switching off occurs in a similar way, i.e. through the menu at the top of the screen. To call it up, swipe down again.
Most modern devices use Android version 4.X.X and lower, so such manipulations will not lead to results. Some models (in particular Samsung and Lenovo) have the ability to turn on a flashlight in their functionality. Lenovo phones have a special standard application called “Flashlight”, which you can find in the list of all applications. If your Lenovo camera is equipped with a flash, then through this application
you can activate it.
In Samsung models, you can activate the flashlight using something called a widget. What is a widget? It is a special graphic add-on that is displayed on the main screen of the phone, which allows you to manage any settings without directly launching the application itself. In some Samsung (and other phones) you can add a flashlight widget to your desktop. To do this, you simply need to follow these steps:
- Place your finger on an empty space on your desktop.
- Wait for the menu to appear. Select "Applications and Widgets"
- In the second tab, find the flashlight widget.
- Hold the icon with your finger and drag it to an empty space.
After these steps, you will have a special button that allows you to quickly turn the flashlight on and off. The widget may be missing (depending on the Android version and device model).
When you hear a call, you need to find the phone very quickly if it is somewhere in the apartment. In poor lighting, the screen brightness may not be enough to detect the smartphone. Some phones with the Android system in the standard settings allow you to turn on the flashlight function when making a call, which works as a rescue beacon. You can enable it on Android when making a call using the following sequence of actions:
- Go to your phone's general settings.
- Select the Accessibility menu.
- Scroll down and then check the box next to “Flash Alert”
- Arrange an incoming call and also check how the LED works.
Thus, when the phone receives an incoming call, the flash will be activated regularly, showing the location of the smartphone. Of course, if the camera with the LED is on the bottom side, then you most likely will not see the flash.
If there is no such item in the settings, naturally, you should not despair, since there are several applications that allow you to activate the flash when making a call. A good example is the Flash on Call app.
It can be adjusted to change the flicker frequency and flash duration. This program offers a very simple interface and is completely free. You can find it to download to your phone in the Google Play store.
As you can see, the scheme is simple. Main elements: current-limiting capacitor, rectifier diode bridge with four diodes, battery, switch, super-bright LEDs, LED to indicate flashlight battery charging.
Well, now, in order, about the purpose of all the elements in the flashlight.
Current limiting capacitor. It is designed to limit the battery charging current. Its capacity for each type of flashlight may be different. A non-polar mica capacitor is used. The operating voltage must be at least 250 volts. In the circuit it must be bypassed, as shown, with a resistor. It serves to discharge the capacitor after you remove the flashlight from the charging outlet. Otherwise, you may get an electric shock if you accidentally touch the 220 volt power terminals of the flashlight. The resistance of this resistor must be at least 500 kOhm.
The rectifier bridge is assembled on silicon diodes with a reverse voltage of at least 300 volts.
To indicate the charging of the flashlight battery, a simple red or green LED is used. It is connected in parallel to one of the diodes of the rectifier bridge. True, in the diagram I forgot to indicate the resistor connected in series with this LED.
It makes no sense to talk about the other elements; everything should be clear anyway.
I would like to draw your attention to the main points of repairing an LED flashlight. Let's look at the main faults and how to fix them.
1. The flashlight stopped shining. There aren't many options here. The reason may be the failure of super-bright LEDs. This can happen, for example, in next case. You put the flashlight on charge and accidentally turned on the switch. In this case, a sharp jump in current will occur and one or more diodes of the rectifier bridge may be broken. And behind them, the capacitor may not be able to withstand it and will short out. The voltage on the battery will increase sharply and the LEDs will fail. So, under no circumstances turn on the flashlight while charging unless you want to throw it away.
2. The flashlight does not turn on. Well, here you need to check the switch.
3. The flashlight discharges very quickly. If your flashlight is “experienced”, then most likely the battery has reached its service life. If you actively use the flashlight, then after one year of use the battery will no longer last.
Problem 1: Doesn't turn on led flashlight or flickers during operation
As a rule, this is the cause of poor contact. The easiest way to treat it is to tighten all the threads tightly.
If the flashlight doesn't work at all, start by checking the battery. It may be discharged or damaged.
Unscrew the back cover of the flashlight and use a screwdriver to connect the housing to the negative terminal of the battery. If the flashlight lights up, then the problem is in the module with the button.
90% of the buttons of all LED lights are made according to the same scheme:
The button body is made of aluminum with a thread, a rubber cap is inserted there, then the button module itself and a pressure ring for contact with the body.
The problem is most often solved by a loose clamping ring.
To fix this problem, just find round pliers with thin tips or thin scissors that need to be inserted into the holes, as in the photo, and turned clockwise.
If the ring moves, the problem is fixed. If the ring stays in place, then the problem lies in the contact of the button module with the body. Unscrew the clamping ring counterclockwise and pull the button module out.
Poor contact often occurs due to oxidation of the aluminum surface of the ring or border on the printed circuit board (indicated by arrows)
Simply wipe these surfaces with alcohol and functionality will be restored.
Button modules are different. Some have contact through the printed circuit board, others have contact through the side petals to the flashlight body.
Just bend this petal to the side so that the contact is tighter.
Alternatively, you can make a solder from tin so that the surface is thicker and the contact is pressed better.
All LED lights are basically the same
The plus goes through the positive contact of the battery to the center of the LED module.
The negative goes through the body and is closed with a button.
It would be a good idea to check the tightness of the LED module inside the housing. It's the same common problem LED lights.
Using round nose pliers or pliers, rotate the module clockwise until it stops. Be careful, it is easy to damage the LED at this point.
These actions should be quite enough to restore the functionality of the LED flashlight.
It’s worse when the flashlight works and the modes are switched, but the beam is very dim, or the flashlight doesn’t work at all and there’s a burning smell inside.
Problem 2. The flashlight works fine, but it’s dim or doesn’t work at all and there’s a burning smell inside
Most likely the driver has failed.
The driver is electronic circuit on transistors, which controls the flashlight modes and is also responsible for a constant voltage level, regardless of battery discharge.
You need to unsolder the burnt driver and solder in a new driver, or connect the LED directly to the battery. In this case, you lose all modes and are left only with the maximum one.
Sometimes (much less often) the LED fails.
You can check this very simply. Apply a voltage of 4.2 V/ to the contact pads of the LED. The main thing is not to confuse the polarity. If the LED lights up brightly, then the driver has failed, if vice versa, then you need to order a new LED.
Unscrew the module with the LED from the housing.
Modules vary, but as a rule, they are made of copper or brass and
The most weakness Similar lanterns have a button. Its contacts oxidize, as a result of which the flashlight begins to shine dimly, and then may stop turning on altogether.
The first sign is that a flashlight with a normal battery shines dimly, but if you click the button several times, the brightness increases.
The easiest way to make such a lantern shine is to do the following:
1. Take a thin stranded wire and cut off one strand.
2. We wind the wires onto the spring.
3. We bend the wire so that the battery does not break it. The wire should protrude slightly
above the twisting part of the flashlight.
4. Twist tightly. We break off (tear off) the excess wire.
As a result, the wire provides good contact with the negative part of the battery and the flashlight
will shine with proper brightness. Of course, the button is no longer available for such repairs, so
Turning on and off the flashlight is done by turning the head part.
My Chinese guy worked like this for a couple of months. If you need to change the battery, the back of the flashlight
should not be touched. We turn our heads away.
RESTORING THE OPERATION OF THE BUTTON.
Today I decided to bring the button back to life. The button is located in a plastic case, which
It's just pressed into the back of the light. In principle, it can be pushed back, but I did it a little differently:
1. Use a 2 mm drill to make a couple of holes to a depth of 2-3 mm.
2. Now you can use tweezers to unscrew the housing with the button.
3. Remove the button.
4. The button is assembled without glue or latches, so it can be easily disassembled with a stationery knife.
The photo shows that the moving contact has oxidized (a round thing in the center that looks like a button).
You can clean it with an eraser or fine sandpaper and put the button back together, but I decided to additionally tin both this part and the fixed contacts.
1. Clean with fine sandpaper.
2. Apply a thin layer to the areas marked in red. We wipe off the flux with alcohol,
assembling the button.
3. To increase reliability, I soldered a spring to the bottom contact of the button.
4. Putting everything back together.
After repair, the button works perfectly. Of course, tin also oxidizes, but since tin is a fairly soft metal, I hope that the oxide film will be
easy to break down. It’s not for nothing that the central contact on light bulbs is made of tin.
IMPROVING FOCUS.
My Chinese had a very vague idea of what a “hotspot” was, so I decided to enlighten him.
Unscrew the head part.
1. There is a small hole in the board (arrow). Use an awl to twist out the filling.
At the same time, lightly press your finger on the glass from the outside. This makes it easier to unscrew.
2. Remove the reflector.
3. Take ordinary office paper and punch 6-8 holes with an office hole punch.
The diameter of the holes in the hole punch matches perfectly with the diameter of the LED.
Cut out 6-8 paper washers.
4. Place the washers on the LED and press it with the reflector.
Here you will have to experiment with the number of washers. I improved the focusing of a couple of flashlights in this way; the number of washers was in the range of 4-6. The current patient required 6 of them.
INCREASE THE BRIGHTNESS (for those who know a little about electronics).
The Chinese save on everything. A couple of extra details will increase the cost, so they don’t install it.
The main part of the diagram (marked in green) may be different. On one or two transistors or on a specialized microcircuit (I have a circuit of two parts:
inductor and a 3-leg IC similar to a transistor). But they save on the part marked in red. I added a capacitor and a pair of 1n4148 diodes in parallel (I didn't have any shots). The brightness of the LED increased by 10-15 percent.
1. This is what the LED looks like in similar Chinese ones. From the side you can see that there are thick and thin legs inside. The thin leg is a plus. You need to be guided by this sign, because the colors of the wires can be completely unpredictable.
2. This is what the board looks like with the LED soldered to it (on the back side). Green color indicates foil. The wires coming from the driver are soldered to the legs of the LED.
3. Using a sharp knife or a triangular file, cut the foil on the positive side of the LED.
We sand the entire board to remove the varnish.
4. Solder the diodes and capacitor. I took the diodes from a broken one computer unit power supply, the tantalum capacitor fell out of some burnt-out hard drive.
The positive wire now needs to be soldered to the pad with the diodes.
As a result, the flashlight produces (by eye) 10-12 lumens (see photo with hotspots),
judging by the Phoenix, which produces 9 lumens in minimum mode.
After working for about a year, my LED Headlight XM-L T6 headlamp began to turn on every once in a while, or even turn off without a command. Soon it stopped turning on completely.
The first thing I thought was that the battery in the battery compartment was failing.
To illuminate the rear LED HEADLIGHT indicator, a regular red SMD LED is used. Marked on the board as LED. It illuminates a plate of white plastic.
Since the battery compartment is located on the back of the head, this indicator is clearly visible at night.
Obviously it won’t hurt when cycling and walking along road routes.
Through a 100 Ohm resistor, the positive terminal of the red SMD LED is connected to the drain of the FDS9435A MOSFET transistor. Thus, when the flashlight is turned on, voltage is supplied to both the main Cree XM-L T6 XLamp LED and the low-power red SMD LED.
We've sorted out the main details. Now I'll tell you what's broken.
When you pressed the flashlight's power button, you could see that the red SMD LED began to shine, but very dimly. The operation of the LED corresponded to the standard operating modes of the flashlight (maximum brightness, low brightness and strobe). It became clear that the control chip U1 (FM2819) is most likely working.
Since it responds normally to pressing a button, then perhaps the problem lies in the load itself - a powerful white LED. Having unsoldered the wires going to the Cree XM-L T6 LED and connected it to homemade block power supply, I made sure it was working properly.
During measurements, it turned out that in maximum brightness mode, the drain of the FDS9435A transistor is only 1.2V. Naturally, this voltage was not enough to power powerful LED Cree XM-L T6, but it was enough for the red SMD LED that its crystal began to glow dimly.
It became clear that the FDS9435A transistor, which is used in the circuit as an electronic key, is faulty.
I didn’t choose anything to replace the transistor, but bought an original P-channel PowerTrench MOSFET FDS9435A from Fairchild. Here is his appearance.
As you can see, this transistor has full markings and the distinctive sign of the Fairchild company ( F ), which released this transistor.
Having compared the original transistor with the one installed on the board, the thought crept into my head that a fake or less was installed in the flashlight powerful transistor. Perhaps even marriage. Still, the lantern did not even last a year, and the power element had already “thrown its hooves away.”
The pinout of the FDS9435A transistor is as follows.
As you can see, there is only one transistor inside the SO-8 case. Pins 5, 6, 7, 8 are combined and are the drain pin ( D rain). Pins 1, 2, 3 are also connected together and are the source ( S ource). The 4th pin is the gate ( G ate). It is to this that the signal comes from the control chip FM2819 (U1).
As a replacement for the FDS9435A transistor, you can use APM9435, AO9435, SI9435. These are all analogues.
You can desolder the transistor using either conventional methods or more exotic ones, for example, using Rose alloy. You can also use the brute force method - cut the leads with a knife, dismantle the case, and then unsolder the remaining leads on the board.
After replacing the FDS9435A transistor, the headlamp began to work properly.
This concludes the story about the renovation. But if I weren’t a curious radio mechanic, I would have left everything as it is. It works fine. But I was haunted by certain moments.
Since initially I did not know that the microcircuit marked 819L (24) is FM2819, armed with an oscilloscope, I decided to see what signal the microcircuit supplies to the transistor gate under different operating modes. It's interesting.
When the first mode is turned on, -3.4...3.8V is supplied to the gate of the FDS9435A transistor from the FM2819 chip, which practically corresponds to the voltage on the battery (3.75...3.8V). Naturally, a negative voltage is applied to the gate of the transistor, since it is P-channel.
In this case, the transistor opens completely and the voltage on the Cree XM-L T6 LED reaches 3.4...3.5V.
In the minimum glow mode (1/4 brightness), about 0.97V comes to the FDS9435A transistor from the U1 chip. This is if you take measurements with a regular multimeter without any bells and whistles.
In fact, in this mode a PWM signal arrives at the transistor ( pulse width modulation). Having connected the oscilloscope probes between the “+” power supply and the gate terminal of the FDS9435A transistor, I saw this picture.
Picture of a PWM signal on the oscilloscope screen (time/division - 0.5; V/division - 0.5). Sweep time is mS (milliseconds).
Since a negative voltage is applied to the gate, the “picture” on the oscilloscope screen is flipped. That is, now the photo in the center of the screen shows not an impulse, but a pause between them!
The pause itself lasts about 2.25 milliseconds (mS) (4.5 divisions of 0.5 mS). At this moment the transistor is closed.
Then the transistor opens for 0.75 mS. At the same time, voltage is supplied to the XM-L T6 LED. The amplitude of each pulse is 3V. And, as we remember, I measured only 0.97V with a multimeter. This is not surprising, since I measured constant voltage with a multimeter.
This is the moment on the oscilloscope screen. The time/division switch was set to 0.1 to better determine the pulse duration. The transistor is open. Don't forget that the shutter is marked with a minus "-". The impulse is reversed.
S = (2.25mS + 0.75mS) / 0.75mS = 3mS / 0.75mS = 4. Where,
S - duty cycle (dimensionless value);
Τ - repetition period (milliseconds, mS). In our case, the period is equal to the sum of switching on (0.75 mS) and pause (2.25 mS);
τ - pulse duration (milliseconds, mS). For us it is 0.75mS.
You can also define duty cycle(D), which in the English-speaking environment is called Duty Cycle (often found in all sorts of datasheets for electronic components). It is usually indicated as a percentage.
D = τ/Τ = 0.75/3 = 0.25 (25%). Thus, in low-brightness mode, the LED is turned on for only a quarter of the period.
When I did the calculations for the first time, my fill factor came out to 75%. But then, when I saw a line in the datasheet on the FM2819 about the 1/4 brightness mode, I realized that I had screwed up somewhere. I simply mixed up the pause and pulse duration, because out of habit I mistook the minus “-” on the shutter for the plus “+”. That's why it turned out the other way around.
In the "STROBE" mode, I was not able to view the PWM signal, since the oscilloscope is analog and quite old. I was unable to synchronize the signal on the screen and get a clear image of the pulses, although its presence was visible.
Typical connection diagram and pinout of the FM2819 microcircuit. Maybe someone will find it useful.
Some issues related to the operation of the LED also haunted me. I had somehow never dealt with LED lights before, but now I wanted to figure it out.
When I looked through the datasheet for the Cree XM-L T6 LED, which is installed in the flashlight, I realized that the value of the current-limiting resistor was too small (0.13 Ohm). Yes, and there is one on the board seat under the resistor was free.
When I was surfing the Internet in search of information about the FM2819 microcircuit, I saw photos of several printed circuit boards of similar flashlights. Some had four 1 Ohm resistors soldered to them, and some even had an SMD resistor marked “0” (jumper), which, in my opinion, is generally a crime.
An LED is a nonlinear element, and therefore a current-limiting resistor must be connected in series with it.
If you look at the datasheet for the Cree XLamp XM-L series LEDs, you will find that their maximum supply voltage is 3.5V, and the nominal voltage is 2.9V. In this case, the current through the LED can reach 3A. Here is the graph from the datasheet.
The rated current for such LEDs is considered to be a current of 700 mA at a voltage of 2.9V.
Specifically, in my flashlight, the current through the LED was 1.2 A at a voltage of 3.4...3.5V, which is clearly too much.
To reduce the forward current through the LED, instead of the previous resistors, I soldered four new ones with a nominal value of 2.4 Ohms (size 1206). I got a total resistance of 0.6 Ohm (power dissipation 0.125W * 4 = 0.5W).
After replacing the resistors, the forward current through the LED was 800 mA at a voltage of 3.15V. This way the LED will operate under a milder thermal regime, and hopefully will last a long time.
Since resistors of size 1206 are designed for a power dissipation of 1/8W (0.125 W), and in maximum brightness mode, about 0.5 W of power is dissipated on four current-limiting resistors, it is desirable to remove excess heat from them.
To do this, I cleaned the green varnish from the copper area next to the resistors and soldered a drop of solder onto it. This technique is often used on printed circuit boards of consumer electronic equipment.
After finalizing the electronic filling of the flashlight, I coated the printed circuit board with PLASTIK-71 varnish (electrical insulating acrylic varnish) to protect it from condensation and moisture.
When calculating the current-limiting resistor, I encountered some subtleties. The drain voltage should be taken as the LED supply voltage. MOSFET transistor. The fact is that on the open channel of the MOSFET transistor, part of the voltage is lost due to the channel resistance (R (ds)on).
The higher the current, the more voltage “settles” along the Source-Drain path of the transistor. For me, at a current of 1.2A it was 0.33V, and at 0.8A - 0.08V. Also, part of the voltage drops on the connecting wires that go from the battery terminals to the board (0.04V). It would seem such a trifle, but in total it adds up to 0.12V. Since under load the voltage on the Li-ion battery drops to 3.67...3.75V, then the drain on the MOSFET is already 3.55...3.63V.
Another 0.5...0.52V is extinguished by a circuit of four parallel resistors. As a result, the LED receives a voltage of around 3-odd volts.
At the time of writing this article, an updated version of the reviewed headlamp appeared on sale. It already has a built-in charge/discharge control board Li-ion battery, and also added an optical sensor that allows you to turn on the flashlight with a palm gesture.
Photo instructions for repairing an LED flashlight. Photos are clickable.Any electrical device can break down. This also applies to LED lights.
The online store provides a guarantee of up to 3 months on everything.
All lanterns are checked upon receipt and again upon sale.
In most cases, flashlight repair is quite accessible to an ordinary person with a standard set of tools.
In 90% of cases, all breakdowns occur due to poor contact in the flashlight circuit.
Problem 1. The LED flashlight does not turn on or flickers during operation
As a rule, this is the cause of poor contact. The easiest way to treat it is to tighten all the threads tightly.
If the flashlight doesn't work at all, start by checking the battery. It may be discharged or damaged.
Unscrew the back cover of the flashlight and use a screwdriver to connect the housing to the negative terminal of the battery. If the flashlight lights up, then the problem is in the module with the button.
.
90% of the buttons of all LED lights are made according to the same scheme:
The button body is made of aluminum with a thread, a rubber cap is inserted there, then the button module itself and a pressure ring for contact with the body.
The problem is most often solved by a loose clamping ring.
To fix this problem, just find round pliers with thin tips or thin scissors that need to be inserted into the holes, as in the photo, and turned clockwise.
If the ring moves, the problem is fixed. If the ring stays in place, then the problem lies in the contact of the button module with the body. Unscrew the clamping ring counterclockwise and pull the button module out.
Poor contact often occurs due to oxidation of the aluminum surface of the ring or border on the printed circuit board (indicated by arrows)
Simply wipe these surfaces with alcohol and functionality will be restored.
Button modules are different. Some have contact through the printed circuit board, others have contact through the side petals to the flashlight body.
Just bend this petal to the side so that the contact is tighter.
Alternatively, you can make a solder from tin so that the surface is thicker and the contact is pressed better.
All LED lights are basically the same
The plus goes through the positive contact of the battery to the center of the LED module.
The negative goes through the body and is closed with a button.
It would be a good idea to check the tightness of the LED module inside the housing. This is also a common problem with LED lights.
Using round nose pliers or pliers, rotate the module clockwise until it stops. Be careful, it is easy to damage the LED at this point.
These actions should be quite enough to restore the functionality of the LED flashlight.
It’s worse when the flashlight works and the modes are switched, but the beam is very dim, or the flashlight doesn’t work at all and there’s a burning smell inside.
Problem 2. The flashlight works fine, but is dim or does not work at all and there is a burning smell inside
Most likely the driver has failed.
The driver is an electronic circuit on transistors that controls the flashlight modes and is also responsible for a constant voltage level, regardless of battery discharge.
You need to unsolder the burnt driver and solder in a new driver, or connect the LED directly to the battery. In this case, you lose all modes and are left only with the maximum one.
Sometimes (much less often) the LED fails.
You can check this very simply. Apply a voltage of 4.2 V/ to the contact pads of the LED. The main thing is not to confuse the polarity. If the LED lights up brightly, then the driver has failed, if vice versa, then you need to order a new LED.
Unscrew the module with the LED from the housing.
Modules vary, but as a rule, they are made of copper or brass and are unscrewed counterclockwise. Unsolder the wires from the star with the LED and remove the driver.
