Motherboard Repairing

Motherboard

COMPONENTS OF Hard Disk

1. IC’S
2. Chips
3. MICRO-RESISTANCE
4. MICRO-CAPACITOR
5. Normal-CAPACITOR
6. PACKAGE
7. FUSE
8. MICRO-COIL
9. Normal –COIL
10. Transistor
11. Diode

Problems of Motherboard

1. Dead
2. Hanging Problem
3. Ram not Access
4. Floppy Port not Work
5. IDE Port not Work
6. Parallel Port not Work
7. Mouse Port not Work
8. Keyboard Port not Work
9. CMOS work  

1. Dead

1. Physically check the motherboard
2. Clean the entire SMD chip & service your main board. Checking burning, blasting or SMD (main IC’s)
3. Clean the ram bank
4. Check all the chip resistance around the SMD chip
5. Check the jumper setting
6. Clear the CMOS
7. Check the CPU temperature
8. Replace the BIOS IC
9. Reinstall the all data cable & power cable
10. Reassemble the CPU

2. Hanging Problem

1. Check the software virus
2. Check the bad sector on hard disk
3. Check the internal & external cache memory from BIOS
4. Check the entire interface card one by one
5. Check the CPU (Processor) jumper setting
6. Check the memory jumper setting
7. Clean the ram & ram bank
8. Clean the entire SMD chip
9. Clean the system board with IP
10. Rewrite the same make & model 

3. Ram not Access

1. Replace the ram
2. Clean the ram & ram bank
3. Clean the area around the ram bank
4. Check the single, packages resistance of ram bank (Value 100 & 220 Ohm’s Resistance)
5. Resold the fuse, single & packages resistance around the ram bank. (Value 100 & 220 Ohm’s Resistance)
6. Resold the ram bank

4. Floppy Port not Work

1. Check the floppy drive is it properly work
2. Check the FDC function Enabled & Disabled from BIOS
3. Check the shortage legs of SMD chip of FDC
4. Resold the FDC port
5. Resold the FDC controller chip
6. Rewrite the BIOS same make & model 

5. IDE Port not Work

1. Check the hard disk & CD Rom is it properly work
2. Check the IDE functions Enabled & Disabled from BIOS
3. Check the buses damage, shortage between IDE ports to SMD chip of IDE
4. Check the IDE controller chip
5. Check the all fuse, single, packages resistance & all components around the IDE ports (330 Ohm’s Resistance)
6. Resold the all fuse, single, packages resistance & all components around the IDE ports (330 Ohm’s Resistance)
7. Resold the IDE ports
8. Resold the IDE controller chip
9. Rewrite the BIOS same make & model

6. Parallel Port not Work

1. Check the LPT port function is Enabled & Disabled from BIOS
2. Check & confirm working function & mode LPT port from BIOS is it correctly set from BIOS
3. Check the three modes of LPT port are ECP, EPP & SSP. Normally select ECP + EPP from BIOS
4. Check & Confirm the select LPT port address 378, IRQ address IRQ7 & DMA address DMA3 is  it correctly set from BIOS
5. Resold the LPT port
6. Rewrite the BIOS same make & model

7. Mouse Port not Work

1. Check the COM port functions Enabled & Disabled from BIOS
2. Check & Confirm the COM I address 3F8H & IRQ address is it  correctly set from BIOS
3. Check the buses damage, shortage between COM port to SMD IC of mouse port
4. Clean the COM ports & SMD IC of Mouse
5. Resold the COM ports
6. Resold the COM ports controller SMD IC
7. Rewrite the BIOS same make & model

8. Keyboard Port not Work

1. Check the jumper
2. Check the keyboard interface controller (loosing & Dry sold)
3. Check the all chip, fuse & coils around the keyboard connector

9. CMOS Error

1. Check the jumper
2. Check the CMOS voltage
3. Check the all chip, fuse & coils around the CMOS connector

Hard Drive Repairing

H.D.D

(Hard Disk Drive)

COMPONENTS OF Hard Disk

1. IC’S
2. Chips
3. MICRO-RESISTANCE
4. MICRO-CAPACITOR
5. PACKAGE
6. FUSE
7. MICRO-COIL

Problems of Hard Disk

1. Dead
2. Not Detect
3. Not Boot But all Proper Work
4. Virus Definition
5. High Level Format
6. Low Level Format

1. Dead

1. Check the power connector & resold it
2. Check the fuse around the power connector
3. Check hot & burn SMD chip
4. Replace the controller card same make & model

2. Not Detect

1. Check the data cable
2. Check the jumper setting
3. Check the dry sold of PCB connector & resold it
4. Check the fuse around the interface connector 
5. Check the 330 Ohm’s micro resistance around the interface connector
6. Check all the resistance of whole card
7. Replace the controller card same make & model

3. Not Boot But all Proper Work

1. Check the operating system is file ok working
2. Transfer the system file again with the help of “SYS” command on DOS. For example: A:\>SYS C:
3. Remove the all partition & rebuild the partition & format it
4. Confirm the hard disk zero track is OK or it have a bad sector on zero track

4. Virus Definition

Virus is software which is used to make or create a problem in software & hardware section. It’s automatically copy & saves in your secondary storage media when you are read & copy any type of infected files virus program is bide software program.

Problem 01: System hang, auto restart computer, auto software corrupted

Solve: If data hard disk used antivirus program for checking & removing virus from hard disk

Problem 02: Hard disk show writing & reading error

Solve: Format it by high level format. For example: A:\>format c:

Problem 03: Hard disk is not high level format

Solve: Remove the partition & turn off computer after few seconds turn on the system then rebuild the partition & format it

Problem 04: Partition is removed but after restar it is present as same condition before remove

Solve: Used disk manager software for remove & make partition

Problem 05: No software is work for making & removes partition

Solve: Used low level format

Problem 06: Hard disk show bad sector

Solve: Used low level format

Problem 07: Hard disk show bad sector in zero track

Solve: Used low level format

5. High Level Format

When you make a new partition from FDISK command you must high level format for using the partition without high level format partition show message invalid media type drive (Partition name) when you try to used the partition.When computer automatically go to scan disk every time you start the computer. If start surface scan hard disk required high level format

For Example:

A:\>format c: (Show bad sector)

A:\>format c:/s (Also make disk bootable)

A:\>format c: /Q (no search bad sector)

6. Low Level Format

Rebuild zero track of hard disk. To remove the logical bad sector format & it all type of partition table.

CD ROM Repairing

CD ROM

(Compact Disk Read Only Memory)

COMPONENTS OF CD ROM

• IC’S
• Chips
• MICRO-RESISTANCE
• MICRO-CAPACITOR
• PACKAGE
• FUSE
• MICRO-COIL

Parts of CD Rom

1. Lens   (+5V DC)
2. Stepper Motor  (+12V DC)
3. Servo motor for CD (+12V DC)
4. Main PCB (Print Circuit board) (+5V DC)
5. Eject Motor (+12V DC)
6. Eject mechanism or Lens mechanism
7. Eject motor / Eject sensor switch
8. Switches for operate front panel
9. Volume variable / switches
10. Stereo pin for real audio sound out
11. Data strip or data cable

Problems of CD Rom

1. Dead
2. Reading Problem
3. Real audio read but VCD & software CD’s not read
4. Servo motor not operate
5. Tray IN/Out eject problem
6. Switches not work
7. CD Rom not detect
8.  Lens problem

1. Dead

1. Check the input +5V & +12V
2. Check the main power connector
3. Check the dry sold & resold the main power connector
4. Check the fuse 0 & 000 Ohm’s resistance around   the main power connector
5. Check the fuse 0 & 000 Ohm’s resistance around the all SMD chip whole the PCB
6. Check hot, burn micro components & SMD chip whole the PCB
7. Replace the PCB with same make & model

2. Reading Problem

1. Clean lens with cotton bud
2. Check the Door / Try switch is it properly work
3. Clean the PCB
4. Clean & resold the main interface connector
5. Check the data cable is it properly connect on pin 1
6. Alignment the lens variable
7. Replace the lens with same make & model

3. Real Audio Read but Vcd & Software
    CD’s not Read

1. Clean the all parts & it’s controller card or PCB
2. Resold the interface connector
3. Clean lens with cotton bud
4. Alignment the lens variablz

4. Servo Motor not Operate

1. Verify the +12V input the CDROM
2. Resold the main power connector
3. Check hot & burn SMD chip of servo motor
4. Check & clean the SMD chip of servo motor
5. Replace the SMD chip of servo motor with same make & model
6. Replace the motor with same make & model
7. Replace the controller card or main PCB

5. Try In / Out & Eject problem

1. Check the data cable is it properly connect on pin 1
2. Check the damage gears of mechanism
3. Check the gears is it properly work & greasing it
4. Replace the rubber belt of eject motor
5. Spray & eject switch change
6. Check, clean & replace the eject switch
7. Spray or change eject door or tray sensor
8. Resold the main power or eject motor connector
9. Resold & clean the eject motor chip
10. Replace the eject SMD chip with same make & model
11. Change the PCB with same make & mode

6. Switches not Work

1. Check the switch
2. Spray the switch & clean it
3. Replace the switch

7. CD Rom not Detect

1. Check the interface data cable
2. Check the jumper setting
3. Check the BIOS setting
4. Check the dry sold of main interface connector of CD Rom & where it connected
5. Check the 0 & 000 OR 33 Ohm’s resistance beside the interface connector
6. Change the PCB with same & model

8. Lens Problem

1. Clean the lens with cotton bud
2. Check the input +5V DC
3. Check the stepper motor properly work
4. Check the strip OR Data cable of lens loosing, dry sold where it connected properly buses damage

RAM Repairing

RAM

(Random Access Memory)

COMPONENTS OF RAM

• IC’S
• MICRO-RESISTANCE
• MICRO-CAPACITOR
• PACKAGE
• FUSE
• MICRO-COIL
• 8 LEG IC

Problems of Ram

1. Dead
2. Some time display ON/OFF
3. Beeping
4. Registry Error
5. Fatal Error
6. Himem.SYS Error
7. Windows Protection Error
8. Some time show the half value of ram
9. Show Binary OR Hexadecimal Code

1. Dead

• Ram physical check
• Service the Ram
• Check loosing & dry sold & resold it
• Check all the micro components

2. Some time display ON/OFF

• If the computer ,display ON and some time display OFF so we clean the ram ped with the help of  “pencil rubber” and wash the bank with the help of chemical but first we clean the ram ped and check the result
• Service the ram completely with the help of chemical

3.Beeping

• If your computer is beeping so you check the ram may be it is not properly connect on the Motherboard OR remove the ram from Motherboard then install the ram in the Motherboard.
• Some time computer is beeping therefore ram is required service.
• Please check the ram in physical way and check all the components of ram.

4.Registry Error

• If the computer always show the registry error it means that your VGA driver is mismatch.
• If the computer always show the registry error it means that your VGA or motherboard or processor are mismatch any of one.
• If the computer show the registry error your ram will heat up.
• Some computer show the registry error due to dusting so you please service the ram completely.
• If the ram is mismatch or incompatible some time computer will produce registry error
• Service the ram completely.
• Please heat up the ram with the help of SMD MACHINE.

5.Fatal Error

• If  your computer produce a fatal error it means that your ram OR processor have a problem mostly fatal error produce due to processor
• In the fatal error screen automatically convert in the blue screen.
• When the component is very heat up then computer produce fatal error.
• When fatal error is display on the computer it means that ram or processor is generate lot of heat.
• If the ram is incompatible or mismatch, computer produce a fatal error and some time not displayed the computer. 

6. Himem.Sys Error

• If the computer is show the himem.sys error it means that 8 leg IC of ram is damage. In this condition system will not boot up in safe mode by pressing F8 key.
• Please replace the 8 legs IC with same number and model.
• If the 8 legs IC is damage in this condition some time display OFF without 8 legs IC & some time display ON without 8 legs IC. That is the reason to on the display without 8 legs IC, it will not detect the himem.sys file because 8 leg IC control the himem file.
• Check the temperature of 8 legs IC and also check it burning and blasting.

7. Windows Protection Error

• When computer show the windows protection error the screen become blank like dos mode
• If the computer show the windows protection error it means that memory is mismatch OR incompatible with motherboard OR processor OR VGA
• When windows protection error produce always ram is heat up
• Some time computer show the windows protection error due to service so you please service the ram completely.

8. Some Time Show the Half Value of Ram

Some time computer show the half value of ram for example; if the computer memory is 128 MB so the computer show the 64 MB in this condition we clean the memory with the help of chemical

9. Show Binary OR Hexadecimal Code

If the computer show the binary or hexa code like 001 ,1A ,2B so you please “clean the ram  ped “ ,  “service the ram completely”, “heat up the ram” with the help of  SMD machine.

Transformer

Transformer

          A transformer is a static piece of apparatus by means of which electric power in one circuit is transformed into electric power of the same frequency in another circuit. It can raise or lower the voltage in a circuit but with a corresponding decrease or increase in current.

Buzzer

An electric signaling device, such as a doorbell, that makes a buzzing sound.

Transistor

The design of a transistor allows it to function as an amplifier or a switch. This is accomplished by using a small amount of electricity to control a gate on a much larger supply of electricity, much like turning a valve to control a supply of water. 

Transistors are composed of three parts – a base, a collector, and an emitter. The base is the gate controller device for the larger electrical supply. The collector is the larger electrical supply, and the emitter is the outlet for that supply. By sending varying levels of current from the base, the amount of current flowing through the gate from the collector may be regulated. In this way, a very small amount of current may be used to control a large amount of current, as in an amplifier. The same process is used to create the binary code for the digital processors but in this case a voltage threshold of five volts is needed to open the collector gate. In this way, the transistor is being used as a switch with a binary function: five volts – ON, less than five volts – OFF. 

Types of Transistor

1. PNP Transistor

2. NPN Transistor

3. Field-Effect Transistor

1.PNP Transistor

NPN Transistor identification in write the “A” & “B”

Checking
Meter Set X10. Meter Negative Probe Connect on Base (-) Leg and Meter Positive Probe Connect on Collector (+) Leg. Meter Show Reading Transistor OK.

2.NPN Transistor

Checking











NPN Transistor identification in write the “C” & “D”

Meter Set X10. Meter Negative Probe Connect on Base (-) Leg and Meter Positive Probe Connect on Collector (+) Leg. Meter Show Reading Transistor OK.

3.Field Effect Transistor

Checking

Step 01

Meter Negative Probe  Transistor Leg (Drain)
Meter Positive Probe    Transistor Leg (Source)

it's show reading

Step 02

Meter Negative Probe  Transistor Leg (Drain)
Meter Positive Probe    Transistor Leg (Gtae)

it's no show reading

Step 03

Meter Negative Probe  Transistor Leg (Drain)
Meter Positive Probe    Transistor Leg (Source)

it's no show reading

Step 04

Meter Negative Probe  Transistor Leg (Gate)
Meter Positive Probe    Transistor Leg (Drain)

it's show reading

Step 05

Meter Negative Probe  Transistor Leg (Drain)
Meter Positive Probe    Transistor Leg (Source)

it's show reading OK

Integrated Circuit

An integrated circuit, or IC, is small chip that can function as an amplifier, oscillator, timer, microprocessor, or even computer memory. An IC is a small wafer, usually made of silicon, that can hold anywhere from hundreds to millions of transistors, resistors, and capacitors. These extremely small electronics can perform calculations and store data using either digital or analog technology.

Digital ICs use logic gates, which work only with values of ones and zeros. A low signal sent to to a component on a digital IC will result in a value of 0, while a high signal creates a value of 1. Digital ICs are the kind you will usually find in computers, networking equipment, and most consumer electronics.

Integrated circuits are usually called IC’s or chip. They are complex circuits which have been etched onto tiny chips of semiconductor (Silicon). The chip is packaged in a plastic holder with pins spaced on a 0.1” (2.54mm) grid which will fit the holes on strip board and breadboards. Very fine wires inside the package link the chip to the pins.

Types of IC

1. SIP IC (Single Inline Package) 

2. DIP IC (Double Inline Package) 

3. PGA Chip (Pins Grid Array) 

4. BGA Chip (Balls Grid Array) 

Fuse

A fuse is a safety device to prevent excess current flowing in an electric circuit. It consists of a thin metal wire of low resistance and low melting point. When an electrical appliance or some other piece of electrical equipment becomes faulty, therefore allowing an excess electric current to flow through its circuit, this causes the wire inside the fuse to melt and thus break the flow of current. 

Fuses, by design are a one-time-use protective device - once they are used ("burn out"), they're worthless. That is why homes typically use circuit breakers: a breaker acts similarly to a fuse in that it opens a circuit when excessive current flows, but - because nothing actually melts inside it - it can then be reset without having to be replaced by a new one, as has to be done for a fuse

Fuse is a piece of wire of a material with a very low melting point. When a high current flows through the circuit due to or a, the wires gets heated and melts. As a result, the circuit is broken and current stops flowing and it’s show by “F”.

Checking

Meter set in X10 then meter one probe is fuse one side & Second probe is second side Connect.Meter show reading it's OK.