Mobile Phone Repairing Testing Methods

Faults in each part, component or section of a mobile cell phone can be repaired fast by using following 2 methods at the time of repairing mobile cell phone. These methods can also be used to find out faulty or damaged parts or components inside a mobile cell phone.

Cold Testing Method: 

When we check the value of resistance using a multimeter at the time of repairing a fault in any mobile phone, it is called cold testing. There is no need to give any power supply to the faulty mobile phone from any equipment such as DC Power Supply or battery during cold testing. Diode Range and Beep Sound from the multimeter is used to find fault in a mobile cell phone using the cold testing method of mobile phone repairing. In this testing method, the RED Probe of the multimeter is connected to the ground of the mobile phone PCB and the BLACK Probe is touched at the testing points of the mobile phone. During the fault finding and repairing process of each part, component or section, following correct values will be received:

1. Ear Phone Connector Tip (+ , -): .500 to .700
2. Loud Speaker / Ringer Connector Tip (+,-): .300 to .600
3. Battery Connector Tip (+): .400 to .500
4. Battery Connector Tip (Sense): above .800
5. Display Connector Supply Pins: .250 to .400
6. Display Connector Signal Pins: .500 to .800
7. Camera Connector Supply Pins: .250 to .400
8. Camera Connector Signal Pins: .600 to .900
9. Key Tip (Row and Column): .400 to .800
10. Charger Connector Tip: .600 to .700
11. Vibrator Motor Connector: .40 to .500
12. Power ON / OFF Switch Point (+): .600 to .900
13. MIC Connector Tip (Analog MIC) (+,-): .700 to .900
14. Battery Charging Out Point (+,-): .300 to .400
15. SIM Card Connector Pin 1 (VSim): .500 to .700
16. SIM Card Connector Pin 2,3,6: .400 to .800
17. SIM Card Connector Pin 4 (GND): .00 (Beep)
18. Micro SD Card Connector Pin 4: .500 to .600
19. Micro Card Connector Pin 6 (GND): .00 (Beep)
20. Micro Card Connector Pin 1,2,3,5,7,8: .600 to .800
21. RTC: .400 to .500
22. Data RX and TX Pins: .600 to .700

Hot Testing:

This is the second method of fault finding and repairing any mobile cell phone. Hot testing method of mobile phone repairing is adopted when the fault cannot be found or when the phone cannot be repaired using the Cold Testing Method. In this method, VOLTAGE of damaged part, component or section of a mobile phone is checked. The fault is found by giving Power Supply to the mobile phone with a Battery of DC Power Supply Equipment such as DC Power Supply. In this method, DCV (DC Volt) range of the Multimeter is selected. The BLACK Probe of the multimeter is connected with the Ground of the Mobile Phone PCB and the RED Probe is touched at the Testing Points. During Hot Testing method, Voltage of different part or sections should be as follows (All Values in Volt):

1. Ear Phone Connector Tip (+ , -) during working: .0 to 2.5
2. Loud Speaker / Ringer Connector Tip (+,-) during working: .0 to 2.5
3. Battery Connector Tip (+): 3.7
4. Display Connector Supply Pins: 1.8 to 2.9
5. Display Connector Signal Pins During Working: .0 to 1.8
6. Camera Connector Supply Pins: 1.8 to 2.9
7. Camera Connector Signal Pins During Working: .0 to 1.8
8. Key Tip (Row and Column) One Side: 1.8 to 2.8
9. Charger Connector Tip: 5 to 6
10. Vibrator Motor Connector Tip During Working: 1.9 to 3.6
11. Power ON / OFF Switch Point (+): 3 to 3.6
12. MIC Connector Tip (Analog MIC) (+,-): 1.8 to 3.0
13. Battery Charging Out Point (+,-): 3.7 to 4.2
14. SIM Card Connector Pin 1 (VSim) When SIM Connected: 1.8 to 3.0
15. SIM Card Connector Pin 2,3,6 During Working: 0 to 2.8
16. Micro SD Card Connector Pin: 2.8
17. Micro Card Connector Pin 1,2,3,5,7,8: 0 to 2.8
18. Data RX and TX Pins: 1.8 to 2.8

Mobile Cell Phone Keypad Not Working Problem and Solution – How to Solve Kaypad Fault in any Mobile Cell Phone

This chapter explains Mobile Phone Keypad Problem and Solution – Mobile Phone Keypad not working and How to Solve Keypad Fault in any Mobile Cell Phone. These problem and solution apply to all brands and make of mobile phones including Nokia, Samsung, iPhone, China Mobile Phones, Motorola, HTC, Sony, Blackberry, Alcatel, Apple, AudioVox, Benefone, Danger, FIC, Hagenuk, Palm, Kyocera, LG, Panasonic, Huawei, ZTE, Spice, Lava, Sony Ericsson, Micromax etc.

What is Keypad in a Mobile Cell Phone?

Keypad in a mobile cell phone is an electronic component or part that helps to enter data like phone numbers and alphabets and operate a mobile phone. Some mobile phones are screen touch and are operated by PDA.

Types of Faults or Problems with Keypad in any Mobile Cell Phone

• No Key Working or only Some Key Working.
• Keys need more pressure to work. Or when pressed a key works continuously.
• One key is pressed and some other key works OR when one key is pressed, some other key works simultaneously.

Mobile Cell Phone Keypad Not Working Problem and Solution – How to Solve Keypad Fault in anyMobile Cell Phone

Mobile Phone Keypad Track Row Column

1. Check Facial of the Keypad.
2. Clean Key pad Tikli and Keypad Points.
3. Keep Multimeter in Buzzer Mode and Check Row and Column of the Keypad. If there is Beep Sound then Pad is OK.
4. Heat or Change Keypad IC / Interface IC.
5. Heat, Reball or Change the CPU.

Note:

1. In a Mobile Phone, when we press a Key and it works very slow then Reload Software to Solve the Problem.
2. In all Nokia Mobile Phones, if only some key works or none of the keys are working then change the Keypad IC to solve the Problem.
3. If Keypad problem is not solved by Hardware, then reload Software in the Mobile Phone to Solve the Problem.

Mobile Phone Fault Finding for Mobile Cell Phone Repairing

In order to repair any mobile cell phone through circuit, we must know the section in which the fault is present and different parts and components present in that particular section. If we know different parts and components present in different sections inside a mobile cell phone then we can easily repair the fault by checking the component.

While doing mobile phone repairing, we can do fault finding if we know different sections inside a mobile cell phone. For Example – If there is Network Problem in a mobile phone then we can easily repair the phone if we know different parts, components and their function in the Network Section.

Following are different electronic parts and components in different sections inside a mobile cell phone:

1. Network Fault: Antenna Switch, PFO, FEM, RF IC, VCO, RX-Filter, TX-Filter, RF Antenna, RF Crystal, External Antenna Socket, Network Signal and Supply Control and Interface Section. If we know about the parts and components present in the Network section and their function then we can easily repair the fault by looking at the code number of the faulty component in the Circuit Diagram and the PCB Layout Diagram. In this way we can easily make good use of circuit diagram for mobile cell phone repairing.
2. Power ON Fault: Battery (3.7V), Battery Connector Jack, Power IC, CPU, Flash IC, S-RAM IC, RF Crystal, RF Clock Section Component, RF IC, Power ON / OFF Trigger Components.
3. Charging Fault: Charger (5-6V), Battery (3.7V), Charger Connector, Charger Volt Fuse, Coil, Charger Over Volt Protector, Charging IC, Power IC, Charging Regulator, Charging Volt Output Components, Charger and Charger Volt Detector Components.
4. SIM Fault: SIM Card, SIM Socket, SIM Signal and Supply Interface Components, Resistance, Coil, Power IC, CPU etc.
5. Ringer Fault: Ringer, Ringer Signal Input and Output Components, Audio Amplifier IC, Power IC, CPU etc.
6. Ear Speaker Fault: Ear Speaker, Ear Speaker Signal Components, Audio Amplifier IC, CPU, Power IC etc.
7. Micro SD Card Fault / MMC Fault: Micro SD Card, Micro Card Connector, Micro Card Detector Switch, Micro Card Detector Signal Components, CPU etc.
8. USB and Bottom Connector fault: USB and Bottom Connector, USB and Signal Interface Connector Components, USB Signal Interface IC, USB Driver IC, CPU etc.
9. Keypad Fault: Key Tip, Key Pad Dot Sheet, Key Signal Filters, Key Signal Varactors, Key Board to Key Connector, CPU etc.
10. Display Fault: LCD, LCD Connector, LCD Supply Components, LCD Signal Interface Filter IC, CPU, LCD Signal Interface Resistance etc.
11. MIC Sound Fault: MIC, MIC Interface Connection, MIC Signal and Supply Components, Power IC, CPU etc.
12. Backlight (LED) Fault: LED, Backlight Driver IC, Backlight Driver Section Components, Power IC, CPU etc.
13. Bluetooth Fault: Bluetooth Antenna, Bluetooth Driver IC, Bluetooth Section Crystal, CPU etc.
14. FM Radio Fault: Fands Free Lead, Hands Free Connector, FM and Bluetooth IC, FM Driver IC, CPU etc.
15. Vibrator Fault: Vibrator Motor, Vibration Supply Components, Power IC, Vibrator Driver IC etc.
16. Touch Panel (PDA) Fault: Touch Panel / PDA Panel, Touch Panel Control IC, CPU, Signal Interface Parts etc.

How to increase the RAM of your Android smartphone

What is RAM (Random Access Memory)?

RAM is what your device uses when it's doing something. For example, when you're editing a photo both the photo and the app you're using to edit it are in the device's RAM; when you finish editing the photo is then saved to your device's storage so it can't get lost. The more RAM you have the more you can do, so for example you can have more browser tabs open, more apps running or more system features doing their stuff.

The problem with RAM is that it isn't always emptied properly, and apps don't always behave. Some apps and system processes run when you don't need them to, and others don't clean up after themselves when they quit. After a while those issues can produce noticeable results such as slow performance, lagging and stuttering, and the odd crash. 

Like internal storage, RAM is a physical component of your device so you can't just stick more in. What you can do, though, is use it more efficiently — or use some clever tricks to create RAM from other kinds of storage.

How to increase your RAM without root access

Now that you know ​​what RAM is, we'll show you how to preserve it. In this first part, we focus on tips for non-rooted devices. For those devices you can't magically add more memory, but you can make better use of what you've got. As a rule of thumb, the more your phone is doing the more RAM is being used, so if you can reduce what's running you can free up more memory for the tasks that really matter. 

Limit widgets and live wallpapers

Widgets and live wallpapers are both pretty greedy when it comes to RAM usage. Many refresh often and occupy bandwidth, while some are continuously active. This can also cause your battery to drain faster. So remember to limit the number of them in effect to optimize your current available memory.

How to root your phone without voiding the warranty.

Disable applications

Some applications take up RAM even if they aren't currently being used, so you're getting all the downsides of unnecessary RAM use without anything to show for it. Organizing which apps should and should not be running in the background can take time, but it's worth it to improve your smartphone performance. 

To disable an application, go to Settings and then Apps or Application Manager. Next, go to the All tab to get the list of all the applications currently on your device. To disable an application, tap on it, then tap Disable and confirm. Be careful not to disable everything and anything, unless you want to end up with an unstable system, but most apps that don't come pre-installed on your handset are pretty safe to disable (or delete entirely if you never use them).

Disable animations

Animations often steal RAM and are quite inessential; you can manage these in the developer options. To enable Developer Options on your device, go to your Settings, then About Phone and then tap on the build number about seven times until it notifies you that you have become a developer. (Please note that this has no negative effect on your device, it just adds the developer options menu in your settings. You just need to be cautious when poking around in there.)

Once you have done this, go back into your phone settings and scroll down to Developer Options. Next, go into the Drawing section and turn off the following options. Your RAM will thank you for it:

 Window animation scale

 Transition animation scale

 Animator duration scale

How to increase your RAM when you have root access

In this section we're going to explain how to increase your RAM with a rooted device. The trick involves creating a partition on your SD card, which will act as a secondary source of RAM. To do this, we will be using the ROEHSOFT RAM Expander (SWAP) app. You can download it here.

Here is the Play Store description of it:

Free SD card memory as a RAM use (SWAP RAM / SWAP MEMORY)

Swapfile RAM expansion up to 4.0 GB (file system limit)

No limit on SWAP partition!

The usual performance degradation when paged not occur with SD card from class-8

Widget for PNP swap (swap on / off swap)

Detailed Memory Information & Analysis

Autorun

​Swappiness kernel parameter set

Easy foolproof use (1 click optimization and automatic calculation)

Supporting Tung all Android devices (root access and Kernelswap support)

You will need a class 4 SD card at a minimum, but for best results you should use a higher class.

Check the compatibility of your device

Before using ROEHSOFT RAM Expander, you will need to check that your device is compatible. Download MemoryInfo & Swapfile Check. Start the app and give it SuperUser rights. Click 'start ramexpander test here' at the bottom of the screen. Select the SD-card or Ext SD-card. Then press 'Click for result'. If 'Congratulations'  appears, your device is compatible with the RAM expander app!

Install the 'Swap'

If you have a compatible handset, download and start the ROEHSOFT RAM-EXPANDER (SWAP) app and start the application. Give it root permissions and select your language (you can choose English, German or French).

Use the slider to select the amount of space you want to allocate to your SWAP partition. Tap 'optimal value' to automatically adjust the settings for the best performance, and 'autorun' should also be enabled. The l

ast thing you need to do is tap 'Swap Activ' to complete the process. 

Increase Internal Memory of Your Phone – 2 Ways

You know Internal memory is such an important part of your Android Phone. All the apps are installed here. The users with high end phones never face a problem with internal memory. But the users with low end phones often are forced to keep only selected apps on their phones as their internal memory is very less. But do not worry know, as rootmyandroid is here for the rescue. In this post I will shoe you that how you could increase your internal memory by using a memory card.

Partition Memory Card:

So as to be bale to use a memory card as an internal memory and add to it, you must first have a partitioned memory card. So there are a number of ways you could be partitioning your memory card. here we will be suing a app named as Link2SD. This app allows your phone to use a part of the memory card as an internal memory and moves those apps on the memory card. But also latest Android versions have the same functionality but thestill the files of those apps are left on the internal memory, and again you have to limit the number of apps you can install on your phone. But if you use Link2SD you could increase your internal memory of phone by no limits. Offcourse you will need a SD card accordingly. So let’s start. There are two ways by which you can partition your memory card, and here they go.

First install the mini Partition Wizard Manager. here is the download link.
insert the card reader into a card reader and open it in computer.
Backup all the files present on your memory card, as in the process of making a partition you need to wipe all the data on the SD card.
Open the tool you installed, and open the Memory Card in it.
Right click on it, and select the “delete” option.


Right click on it again, and now select the option “Create New”, Create a “FAT32″ partition. This will be the part of the memory card, where all your media files will be stored.
Then Select “Create as: Primary”


Then, create an ext2/ext3/ext4 partition ( if you are on stock ROM choose ext2). This is the place all your apps will be stored.
Then select “Create as:primary”  (Make sure that it is both set as primary, because it will not be working if it is not set to primary).
And now click on the “Apply” button on the top corner, and wait for the changes to take place. Congrats you have successfully partitioned the memory card by first method.

How to find lost iPhone

If your iPhone, iPad, or iPod touch is lost or stolen
If you lose your iPhone, iPad, or iPod touch or think it might be stolen, these steps might help you find it and protect your data.


If Find My iPhone is turned on, you can use it to find your device.


If Find My iPhone isn't on, change your passwords and report the device as missing.

If Find My iPhone is enabled on your missing device

You can use Find My iPhone to find your device and take additional actions that can help you recover it and keep your data safe.
Sign in to icloud.com/find on a Mac or PC, or use the Find My iPhone app on another iPhone, iPad, or iPod touch.
Find your device. Open Find My iPhone, and select a device to view its location on a map. If the device is nearby, you can have it play a sound to help you or someone nearby find it.
Turn on Lost Mode. Using Lost Mode, you can remotely lock your device with a four-digit passcode, display a custom message with your phone number on your missing device's Lock screen, and keep track of your device's location. If you added credit or debit cards to Apple Pay, the ability to make payments using Apple Pay on the device will be suspended when you put your device in Lost Mode.

Report your lost or stolen device to local law enforcement. Law enforcement might request the serial number of your device. Find your device serial number.
Erase your device. To prevent anyone else from accessing the data on your missing device, you can erase it remotely. When you erase your device, all of your information (including credit or debit cards for Apple Pay) will be deleted from the device, and you won't be able to find it using Find My iPhone. After you erase a device, you can't track it. If you remove the device from your account after you erase it, Activation Lock will be turned off. This allows another person to activate and use your device.
If you use Family Sharing, any family member can help locate another member’s missing device. Just have your family member sign in to iCloud with their Apple ID, and you can find any device associated with that Family Sharing account.
What if your iOS device is off or offline?
If your missing device is off or offline, you can still put it in Lost Mode, lock it, or remotely erase it. The next time your device is online, these actions will take effect. If you remove the device from your account while it's offline, any pending actions for the device will be cancelled.
How do you turn off or cancel Lost Mode?
You can turn off Lost Mode by entering the passcode on your device. You can also turn off Lost Mode on iCloud.com or from the Find My iPhone app.
If Find My iPhone isn't enabled on your missing device

If you didn't turn on Find My iPhone before your device was lost or stolen, you can't use it to locate your device. However, you can use these steps to help protect your data:
Change your Apple ID password. By changing your Apple ID password you can prevent anyone from accessing your iCloud data or using other services (such as iMessage or iTunes) from your missing device.
Change the passwords for other internet accounts on your device. This could include email accounts, Facebook, or Twitter.
Report your lost or stolen device to local law enforcement. Law enforcement might request the serial number of your device. Find your device serial number.
Report your lost or stolen device to your wireless carrier. Your carrier can disable the account, preventing phone calls, texts, and data use.

Find My iPhone is the only way that you can track or locate a lost or missing device. If Find My iPhone isn't enabled on your device before it goes missing, there is no other Apple service that can find, track, or otherwise flag your device for you.

Counting Legs or Pins of IC

Any mobile phone PCB has several IC or Integrated Circuit. These are SMD or Surface Mount Electronic Components. Before understanding how to count legs or pins of any IC, let us learn about IC.

What is an IC?

An IC is an electronic component made up of combination or integration of several other electronic components like resistor, capacitor, coil, diode, transistor etc.

How Many Types of IC are There?

There are mainly 2 types of ICs:

1. Leg-Type IC: This type of IC has legs or pins. These types of ICs are again divided into different categories but we will not discuss it here because it has nothing to do with mobile repairing.
2. Ball-Type IC: This type of IC has BGA (Ball Grid Array) underneath the IC. These types of ICs are again divided into different categories but we will not discuss it here because it has nothing to do with mobile repairing.

How to Count Legs or Pins of Leg-Type IC?

Counting of leg-type IC starts in Numerical Digit in Anticlockwise Direction starting from the Nose Point or Cut Point.

How to Count Balls of Ball-Type IC?

Counting of Ball-type IC is done in Both Clockwise and Anti-Clockwise Direction. Rows are counted in Digit Numbers (1, 2, 3, 4…) in Clockwise Direction. Columns are counted in Alphabet (A, B, C, D…) in Anti-Clockwise Direction.

NOTE: When counting Columns, “I” and “O” are omitted because they look like “1” and “0”.

Current | Electric Current | AC (Alternate Current) | DC (Direct Current)

What is Current or Electric Current?

Current or electric current is flow or charge (electrons that are negatively charged) from one medium to another through a conductor medium like copper wire, aluminum wire, circuit, electric wiring etc.

What is the SI Unit of Current?

The SI unit of current is ampere.

How is Electric Current Measured?

Electric current is measured using an ammeter.

Types of Electric Current

Electric current is of 2 types – AC or Alternating Current and DC or Direct Current.

What is DC Current?

DC Current Symbol

DC or Direct Current is the flow of electric charge in one direction. This is called unidirectional flow of electric charge. DC current is produced by devices like battery, thermocouple, solar cell, dynamo etc. DC current is also called galvanic current.

What is AC Current?

 AC or Alternate Current is the flow of electric charge that periodically reverses direction in a waveform.

AC Current Symbol

Current in Mobile Phone

The circuit of a mobile phone PCB works on DC current. The battery provides DC current to the circuit.

JUMPER

How to Jumper in Mobile Phone Repairing

Most mobile phone repairing is done by doing jumper. Different parts of a mobile cell phone like display, keypad, speaker, microphone, LED lights, different ICs, different small parts and electronic components, all have different jumper settings. It is important to first track the fault or missing track and then do the jumper.

Mobile Phone Repairing Tools You Will Need to Dumper

1. Mobile phone jumper wire.
2. Soldering iron.
3. Solder wire.
4. Blade cutter.
5. Multimeter.
6. Soldering flux.
7. PCB holder.
8. Tweezers.

How to Jumper

1. Disassemble mobile phone and place it on a PCB holder.
2. Using a multimeter, check track and find the fault or the missing track that need jumper.
3. Apply liquid soldering flux to the points where you need to solder jumper wire.
4. Cut jumper wire to desired length and remove its lamination using blade cutter.
5. Hold one end of the jumper wire and solder it to one point of the faulty circuit track. Use a good quality tweezers to hold the wire and good quality of soldering iron and solder wire to solder.
6. Now hold the other end of the jumper wire and solder to the other point of the track
7. Using a multimeter check the jumper.

Mobile Cell Phone Dead Problem and Solution – How to Repair Dead Mobile Cell Phone

This chapter explains Mobile Phone Dead Problem and Solution –How to Repair a Dead Mobile Cell Phone. These problem and solution apply to all brands and make of mobile phones including Nokia, Samsung, iPhone, China Mobile Phones, Motorola, HTC, Sony, Blackberry, Alcatel, Apple, AudioVox, Benefone, Danger, FIC, Hagenuk, Palm, Kyocera, LG, Panasonic, Huawei, ZTE, Spice, Lava, Sony Ericsson, Micromax etc.

What is a Dead Mobile Cell Phone?

A Dead mobile phone is a hand set that does not get switched ON.

How Does a Mobile Cell Phone Gets Dead?

• If the mobile phone gets dropped down on the floor or on some hard surface.
• If the mobile phone gets wet or is dropped in rain or water.
• If there is any kind or short ( in + and – )

Mobile Cell Phone Dead Problem and Solution – How to Repair a Dead Mobile Cell Phone

1. Remove the battery and see if it gets charged or not. Check voltage using a Multimeter. Voltage must be above 3.7 Volt. Use a Battery Booster to Boost the Power of the Battery and Charge it again.
2. Check Battery Point and Battery Connector. Clean Battery Point and Battery Connector to remove any carbon deposits.
3. Resold or change the Battery Connector.
4. Insert charger and se if the “Battery Charging” appears on not. If there is icon of “Battery Charging” but the mobile phone does not gets switched ON then check ON / OFF Switch. Voltage of ON / OFF Switch must be 2.5 to 3.5 Volt (DC). Clean or change the ON / OFF Switch. Check track of ON / OFF Switch and Jumper if required.
5. If the charging icon is not there then check voltage of ON / OFF Switch. If the voltage is between 2.5 to 3.7 Volts DC, then RELOAD Software in the Phone (Software Flashing).
6. If the phone does not gets switched ON even after reloading software then Heat the C.P.U, Power IC and Flash IC.
7. If there is no voltage on the ON / OFF Switch then check track of the ON / OFF Switch. Jumper if required.
8. If the problem is not solved then heat, Reball or change the Power IC and CPU to fix the problem.
9. Keep the Multimeter on Buzzer Mode and Check +_ and – of the Battery Connector. If there is Buzzer Sound then the Set is short. If there is short at the Battery Connector then clean the PCB with thinner. Heat the PCB.
10. If this does not fix the set dead problem then remove the PFO and check for short. If there is short then replace the PFO.
11. Remove the charging connector and check for shorting. If there is short then change the connector.
12. Remove the charging IC and check for shorting. Change if required.
13. Remove the Bluetooth IC and check for shorting. Replace if required.
14. Remove the Power IC and check for shorting. Replace with a new one if required.
15. Remove the CPU and check for shorting. Replace if required.
16. Remove all the Big Electrolytic Capacitors and check one by one. Replace capacitors if required.

Note:

1. Some mobile phones get dead if the RTC (Real Time Clock) is faulty. This happens mostly in China Mobile Phones. Change the RTC to fix the problem.
2. If the mobile phone gets hang after reloading software then change the RTC.
3. If the set is still dead then check by replacing the 26 MHz Crystal Oscillator.

Mobile Cell Phone SIM Not Working Problem and Solution – How to Solve SIM Fault in any Mobile Cell Phone

This chapter explains Mobile Phone SIM Problem and Solution – Mobile Phone SIM not working and How to Display Fault in any Mobile Cell Phone. These problem and solution apply to all brands and make of mobile phones including Nokia, Samsung, iPhone, China Mobile Phones, Motorola, HTC, Sony, Blackberry, Alcatel, Apple, AudioVox, Benefone, Danger, FIC, Hagenuk, Palm, Kyocera, LG, Panasonic, Huawei, ZTE, Spice, Lava, Sony Ericsson, Micromax etc.

What is SIM in a Mobile Cell Phone?

SIM stands for Subscriber Identification Module. In a mobile cell phone it is an electronic component or part that helps identification of the User.

Types of Faults or Problems with SIM in any Mobile Cell Phone

• SIM is inserted but still there is a message saying “Insert SIM”.
• The Mobile Phone goes OFFLINE when the SIM Card is inserted.
• SIM works for sometime and then it stops working.
• There is a message that says “Invalid SIM”.

Mobile Cell Phone SIM Not Working Problem and Solution – How to Solve SIM Card Fault in any MobileCell Phone

1. Check settings and see if the mobile phone is in Flight Mode or Not. If it is in “Flight Mode” then change the Mode to Normal.
2. Clean SIM Card Tips and SIM Connector.
3. If the problem is not solved then change the SIM Card and Check.
4. If the problem still persists then Change the SIM Connector.
5. If you still do not find solution to the problem then Check Track of the SIM Section. Refer to the Diagram of the Particular Model of the Mobile Phone. Books with Diagrams of Tracks are available in the Market and on the Internet.
6. If the problem is still not solved then Heat or Change the SIM IC.
7. Finally, Heat, Reball or Change the Power IC.

Note:

• Check if the IMEI Number of the Mobile Phone is Good or Corrupt. To check the IMEI Number, Dial*#06#. If the IMEI Number is something like – 35826********220 OR *************??? OR************000? OR ***************? Then the IMEI Number is Corrupt. Reload the IMEI Number to solve the SIM Problem.
• Check BSI Point of the Battery. The Middle Pin is the BSI. Change the Battery and Check. If the Display shows “Not Charging” and at the same time there is SIM Card Problem then it is caused because of BSI Problem of the Battery or the BSI Track of the PCB.
• If you need to change the SIM IC and SIM IC is not available then you can do jumper. The function of the SIM IC is just to complete the circuit.

Mobile Phone No Network Signal Problem and Call Drop Problem and Solution

What is Mobile Network?

A cellular network or mobile network is a communication network where the last link is wireless. The network is distributed over land areas called cells, each served by at least one fixed-location transceiver, known as a cell site or base station. This base station provides the cell with the network coverage which can be used for transmission of voice, data and others. In a cellular network, each cell uses a different set of frequencies from neighboring cells, to avoid interference and provide guaranteed bandwidth within each cell.

When joined together these cells provide radio coverage over a wide geographic area. This enables a large number of portable transceivers (e.g., mobile phones, pagers, etc.) to communicate with each other and with fixed transceivers and telephones anywhere in the network, via base stations, even if some of the transceivers are moving through more than one cell during transmission.

Cellular networks offer a number of desirable features:

• More capacity than a single large transmitter, since the same frequency can be used for multiple links as long as they are in different cells
• Mobile devices use less power than with a single transmitter or satellite since the cell towers are closer
• Larger coverage area than a single terrestrial transmitter, since additional cell towers can be added indefinitely and are not limited by the horizon

Major telecommunications providers have deployed voice and data cellular networks over most of the inhabited land area of the Earth. This allows mobile phones and mobile computing devices to be connected to the public switched telephone network and public Internet. Private cellular networks can be used for research or for large organizations and fleets, such as dispatch for local public safety agencies or a taxicab company.

Mobile Phone No Network Signal Problem and Call Drop Problem and Solution – No or week network signal or call drops. Learn how to solve and fix this problem.

Mobile Phone Network Signal Problem

There are situation when a mobile cell phone of any brand including Samsung, Nokia, LG, iPhone, Micromax, China Mobile Phones etc may problems such as No ow week Network and Auto Call Drop.

There can be different symptoms, reasons and solutions to identify, solve and fix the problem.

How to Solve and Fix Mobile Cell Phone No Network Problem and Call Drop Problem.

1. Check the SIM Card. See if the SIM is OK or not. Insert the SIM Card in other mobile phone and see it the Network Problem and Call Drop Problem is still there or not.
2. Also try to insert another SIM Card in the Same Mobile Phone which is giving the problem.
3. If there is problem with the SIM Card then try to change or replace it.
4. If the problem is still not solved then upgrade the Software / Operating System (OS) to the latest version. Also Rewrite the IMEI Number of the Mobile Cell Phone.
5. If the problem is not solved then you may have to change the Mobile Phone PCB.

Wi-Fi Wireless Connection Problem and Solution in Mobile Cell Phone

What is Wi-Fi?

Wi-Fi or WiFi is a local area wireless computer networking technology that allows electronic devices to connect to the network, mainly using the 2.4 gigahertz (12 cm) UHF and 5 gigahertz (6 cm) SHF ISM radio bands.

The Wi-Fi Alliance defines Wi-Fi as any "wireless local area network" (WLAN) product based on the Institute of Electrical and Electronics Engineers' (IEEE) 802.11 standards. However, the term "Wi-Fi" is used in general English as a synonym for "WLAN" since most modern WLANs are based on these standards. "Wi-Fi" is a trademark of the Wi-Fi Alliance. The "Wi-Fi Certified" trademark can only be used by Wi-Fi products that successfully complete Wi-Fi Alliance interoperability certification testing.

Many devices can use Wi-Fi, e.g. personal computers, video-game consoles, smartphones, digital cameras, tablet computers and digital audio players. These can connect to a network resource such as the Internet via a wireless network access point. Such an access point (or hotspot) has a range of about 20 meters (66 feet) indoors and a greater range outdoors. Hotspot coverage can be as small as a single room with walls that block radio waves, or as large as many square kilometres achieved by using multiple overlapping access points.

Wi-Fi is less secure than wired connections, such as Ethernet, precisely because an intruder does not need a physical connection. Web pages that use TLS are secure, but unencrypted internet access can easily be detected by intruders. Because of this, Wi-Fi has adopted various encryption technologies. The early encryption WEP proved easy to break. Higher quality protocols (WPA, WPA2) were added later. An optional feature added in 2007, called Wi-Fi Protected Setup (WPS), had a serious flaw that allowed an attacker to recover the router's password. The Wi-Fi Alliance has since updated its test plan and certification program to ensure all newly certified devices resist attacks

Wi-Fi Wireless Internet Connection Problem

There are situation when a mobile cell phone of any brand including Samsung, Nokia, LG, iPhone, Micromax, China Mobile Phones etc may give problems such as Wi-Fi wireless internet connection.

There can be different symptoms, reasons and solutions to identify, solve and fix the problem.

How to Solve and Fix Mobile Cell WiFi Wireless Internet Connection Problem

1. Enable Wi-Fi and check if it is working or not. Make sure you are connected to a wireless Wi-Fi Network. Make sure the password is correct. 
2. If the Wi-Fi cannot be enabled and you are not able to use or access internet then there could be problem with the Mobile Phone PCB or the WiFi Controller IC. You may have to replace the PCB. 
3. If the Wi-Fi can be enabled then there is no problem with the PCB. Just upgrade the software / operating system (OS) of the mobile phone or smartphone to the latest version. This should solve the problem.