Get now for only $14.99Advance Technical Chip-Level
Repair of Laptops MotherboardComponent Level Laptop Motherboard Repair + 2000 schematic + more like 20 free ebook

This is a fully comprehensive instructional course in getting into the business of repairing all makes of laptops. Chip-level Training will be customized for yourpresent knowledge of electronics. If you go through the fundamental track , all the power electronic components will be introduced before we move to the logics section. After you become comfortablewith power electronics the logic session follows . It is an intensive coverage into the intricate details of chip-level service of the laptops. This involves detailed circuit tracing , signalanalysis , replacement of SMD devices and all the tips and tricks our service engineers acquired from the years of experiences. the session makes you confident enough to chip-level service the newgeneration notebooks from Lenova , Compaq, HP , Toshiba ,Sony and the like .

Service Technicians entering into the Laptop training course must have experience in the following disciplines

• must be comfortable in using desktop systems and peripherals
• must have an above average knowledge about all the internal components and operation of the system
• comfortable with installing and managing various operating systems.
• managing the hard disk subsystem with formatting and partioning.
• installation and configuration of computer components like add-on devices

Ready To Learn A New Skill Online?

Question:

Would love to know how you diagnose motherboards on a component level. What tools do you use?

Answer:

I find it is very hard to explain this. actually, it is very simple and can be described in two words: current and singal. read the current change during booting tellsyou where the machine stopped. check the singals on the different part of motherboard tells what is wrong or what may missing.

Tools are: smd rework station, bga rework station, power supply has current meter. all the rest tools you can find in any radio tv repair shop.ofcourse all the datasheets for the components, especially the schematic diagram, you will find it much difficult without it.

Question:

What are common faults on mainboards?

Do certain components fail? Is there a trend as to which parts fail quite often?

Answer:

Different maker/model has different common fault. Toshiba S1 is vga chip, and can't be repaired(well, almost can't be repaired because the pcb quality is not very goodso successful rate is very low).
HP DV2000, 6000, 9000, compaq v3000, v6000, dell 1210, all those use nvidia chips have problem on vga chip or north bridge. easy to repair but have to make fan keep spinning after repaired, otherwisewill break down in 1 or 2 week again.

hp nx5000, cpu pwm chip dry joint. acer 290, cpu pwm dry joint.
hp dv1000, compaq m2000 protection circuit easy to blow up.
ibm t40 vga dry joint problem.
These are just few of them. every machine has its own common fault. but dry joint is the common problem for all machines. Motherboard repair is not as difficult as people thought, i think much easerthan repair a tv.

Question:

Dell 1525 Inspiron that says system does not recognize the installed battery this system will not charge the battery.

Answer:

Charging battery in Dell laptop involves two major chips: EC(or someone call it super IO), PWM chip for battery charging. BIOS has no part of charging. Batterycommunicate with EC through SMB(system management bus??) and EC controls charging PWM. Fix charging problem is very hard in laptop repair, you must fully understand schematics, where all the signalscome from and where to go.
Today's laptops are less and less with programmed EC, Dell 1525 has no programmed EC so it can be replaced with same model.

Question:

How i fix a DV6 with power problem. The problem of machine is it cannot power up at all.

Answer:

Doing routine check:
1. system power: 3V, 5V all presented - ok
2. NBSWON signal: 3.3V presented - ok
3. press power button, NBSWON pull down to 0V, ok
4. check DNBSWON while press power button, no response. - problem.
in here I made a mistake, I didn't pay attention of the voltage of DNBSWON, this mistake waste me the next few days time. It should be 3.3V, but only about 1V.

Change EC as usual, because I thought the EC has problem. Then the big trouble comes - it auto power up once I plug in the power but stop in 0.04A current. Check andfind no S5_ON signal, which indicate south bridge has problem, so change south bridge. But still same problem and still no S5_ON. I find that the EC I change is kb3926A rather than kb3926C. In mostcase, this is no problem but in very rare occation...
So I find a 3926C and put on. Now the motherboard is back to the same problem while I first start to check! So I change a wrong EC and this time I change a correct one, and also EC has noproblem!

Because EC will start to read bios once the power plug in(not as people think, once you press power button). I check BIOS chip, BIOS_CS should have a countinue waveform but it just one stright line. BIOS chip is faulty, I replace the BIOS chip and it works perfect.

More Like 20 E-Book For FreeSOME OF THEM:Laptop Power On Detail Step with timing e-bookSmd Soldering Guide e-bookSystem Component Troubleshooting e-bookHow To Flash Bios e-bookHard Disk PCB Circuit Repair Data Recovery e-bookTroubleshooting Network Problem e-bookReballing Process e-bookHow to replace battery cells inside laptop battery e-bookEtc.Free 1000+1000 LaptopSchematic MotherboardCircuit Diagrams