why your laptops can't start

why your laptops can't start


First, we first check whether the power adapter Apple Laptop Battery voltage output (typically the DC power supply for laptop: Toshiba 15V, IBM 16V,, Compaq 18.5V, the majority of 19V, DELL 20V, mobile PC typically 12V), and if so, further investigation generates 12V, 5V, 3.3V power supply chips with or without base voltage and standby voltage of 5V, there is the battery charger has no electricity, CPU power circuitry have 3.3V power supply, there is no reference Laptop Battery voltage, Power Management IC side through the FET gate drive, whether high or low power, it was not prepared according to standby, do not have insurance check resistors are not bad, as well as filter capacitor, there is no bad!

For battery charging and dissatisfaction with electricity, but also decided that the battery is good, most likely the following situations, for reference:

1. The early termination of the charging circuit

2. MOSFET and boost capacitor damage

3. Chip control parameters for a bad cause, only for the Apple A1175 Battery chips

If discharge can not be charging boost capacitors and FET no bad, only for the chips. . Chip is not easy in general bad. .

Does not boot failure:

1 to see if there is no obvious visible failures. If there is no place burned, deformation, crack and so on. Smell there is no place to paste a burnt taste.

2, start to listen to there normal or abnormal sound from over there.

3, detection in the absence of specialized tools can only be Apple A1185 Battery the case whether the blown resistance multimeter Cece insurance, there are no obvious short-circuit and so on. CPU, memory is not good contact and so can Cece. Note that when power can not be artificially caused by short circuit damage.

Screen display is not normal:

Failure appears to be from the screen or the screen wire may be problems:

1, check power supply on the motherboard screen is normal, the voltage a few volts usually 1:00, 2:00 a few volts, 3 points a few volts. IBM machine because of high-voltage power supply board are, and on the LCD screen with a data line, so there are several groups of a few volts for Apple M9324 Battery the 5-point, 10-volt or so voltage.

2, if there is electricity, check the screen then import Office, with the multimeter to the amount of voltage. Voltage value above! If you do not have voltage is a line on the screen is certainly fault. For a screen line or a line with the same pressure line can fly, if you can be able to troubleshooting. If you still fail to exist, the screen may also be defective, and that is rare, very few exist!!! To determine the voltage to the screen to Apple M8403 Battery, normal, will have to repair the screen. On-screen signal processing on blocks of micro-chip. The chip with an oscilloscope to see the waveform after processing is correct, sub-three walk (1), if substandard, you can change block of the same model chip. If combined, they check the surrounding capacitors. Second, if does not work, only for block-screen, and because it is the pressure line loose screen. Third, if there is no electricity, will have to check whether the graphics output voltage stability, this part of the voltage to a signal processing chip, and then output to the screen line. If you still voltage or Apple M7318 Battery normal, we can determine is a piece of chip failure. In exchange for the same model chip can have a voltage output to the screen the line, after which you can then check the same with the second.

Motherboard Power Failure:

First, check the motherboard does not power on, measure the power management chip 1632 or 1631 (most of these two chips) and fifth legs have 5 volts, 21,22 feet have 16 volts and 5 volts. See if there is 2951 in this eight-legged film Cece he has 5 apple PowerBook G3 Battery volts.

Does not boot repair methods:

1. To exclude power outlet, the module loose their connections and attachments on the motherboard, cpu loose. Cold solder joint and so on.

2. Check the main power supply fuses, it Apple PowerBook G4 Battery burned, if burning or play a positive resistance value can not be too small or short-circuit response can be ignored! (Excluding electrical fault isolation to enter the next step)

3. Measurement, 3.3v/5v Generation Circuit / cpu the main power supply circuit / battery charging circuit whether the supply voltage = adapter voltage without the corresponding circuit repair.

4. Power On Button

5. Normal supply of electricity should just take a look at the clock circuit is no electricity for more than Apple PowerBook G4 15inch Battery PII machines generally have two power supply 3.3v 2.5 from 3.3v/5v generating circuit and the outer core cpu voltage generator) to find the edge of the circuit test points The chip capacitor. 5. Comparison of headache did not chip reset circuit is not easy to find information on the hard drive on the pc card slot to use the reset pin (do not tell me you do not know what!!!) simple judgments about the whole thing

6. Essentially, it powered the clock reset to normal we will have to refresh BIOS, but the brush must be backed up Apple A1012 Battery before ah.