Repair of HP TPN-I133 Pulling Adapter Laptop Screen Crash

HP TPN-I133 unplugged the adapter, the notebook screen crashed, and the motherboard was removed. It was observed that a resistor on the motherboard was moldy, the board was washed with water, the power supply circuit of the memory was normal, and the battery used for the adapter was normal.

Machine model: HP TPN-I133 notebook

Fault phenomenon: the notebook screen crashes.

Maintenance process:

An HP TPN-I133 notebook works normally with the adapter, and the battery is charged. When the adapter is unplugged, the notebook screen crashes, every time.

There are many reasons for the crash of the screen, such as memory, CPU, hard disk, power supply, etc. It is no problem to replace the memory and hard disk, and it will also happen under the BIOS. No problems were found in the preliminary measurement.

Remove the motherboard and observe that only USB port on the motherboard has cockroach droppings. Look carefully. One of the resistors is moldy. Wash the board with water, test the memory power supply circuit is normal, and use the adapter battery is normal.

Maintenance of HP TPN-I133 Pulling Adapter Laptop Screen Crash Figure 1

After a day’s test, the battery won’t turn on again, and it’s the same to unplug the adapter.

Measure the power supply of the memory. When the adapter is unplugged and fails, the voltage is 1.16V. When the adapter is plugged in, it is 1.22V, but 1.16 V should be abnormal. Remove the moldy resistor and measure 356K K..

Maintenance of HP TPN-I133 unplugging adapter notebook screen crash Figure 2

G5388 memory power supply circuit, find other machine drawings for reference, the chip’s seventh pin VDDQ_TON is 510K K.

Maintenance of HP TPN-I133 Pulling Adapter Laptop Screen Crash Figure 3

This resistance is to change the switching frequency, directly change the resistance of 510K, normal, voltage 1.22V, start-up test, perfect start-up, troubleshooting, and maintenance is over.