iPhone Wi-Fi circuit repairing

This video mainly explains how to find the 2.4G and 5G signal lines of iPhone 11 Wi-Fi circuits

Step 1, find the Wi-Fi location number in the component map

Step 2, search for the Wi-Fi location number in the schematic diagram

Step 3, find the corresponding antenna pin in the schematic diagram

Step 4, search for the pin identification in the schematic diagram,

find the connected components, and finally find the antenna screw post

We can also jump to the bitmap according to the name to view the connected components

When checking the maps, first open the iPhone 11 component map, circuit diagram, and bitmap

Find the Wi-Fi location number in the component map

Then search for the Wi-Fi location number in the schematic diagram

After finding the Wi-Fi chip, find the corresponding signals

In the functional block diagram, TX_5G_C0 represents 5G upper antenna transmission

RX_5G_C0 represents 5G upper antenna receiving

Receiving and transmission signals are connected to the filter

After reaching the filter, the antenna signal will be shared

TX/ RX_5G_C1 represents Wi-Fi 5G lower antenna

2G_ANT_C0 represents 2.4G upper antenna

2G_ANT_C1 represents 2.4G lower antenna

When the mobile phone is searching for a signal,

it mainly relies on the upper antenna to search for the signal,

and the lower antenna is only an auxiliary function

If the Wi-Fi has a weak signal problem, we only need to find the upper antenna line

When repairing the weak Wi-Fi signal, if it is found that the 5G signal is weak,

then we need to find the line from the 5G antenna to the antenna connector

The 5G antenna circuit has transmission and receiving pins

Let's find the receiving pin first

Pin 52 of the Wi-Fi chip is the receiving pin of the 5G upper antenna

Search for the line name

It is connected to resistor R9027

After passing through the resistor,

we have to search for the name of the back end of the resistor

In the schematic diagram, the box that does not identify the coordinates of the pin is the signal conversion box,

we do not need to check

After the signal passes through the resistor, it is connected to the resistor R362_W,

and then connected to pin 14 of U_5G_UW

The chip is an antenna filter

The 5G transmission signal will also be connected to the chip

Pin 50 of the Wi-Fi chip is the transmission signal for 5G

After the line comes out of the Wi-Fi chip, it is connected to the resistor R233_W

After passing through the resistor, we search for the signal name on the back end of the resistor

After the signal passes through the resistor, it is connected to the resistor R363_W,

and then connected to the pin 16 of U_5G_U_W

The transmission signal of the 5G upper antenna is also connected to the chip

The 6th pin of the chip is the antenna pin, ANT,

and the other pins are control pins or detection pins, we do not need to search

We need to continue to look down from pin 6

Search for the name of pin 6, it is connected to the resistor R2321_K,

and connected to FLANT_4 after passing through the resistor

The chip is an antenna switch, pins 3 and 7 are the pins that need antenna,

and pin 1 is the antenna pin ANT

So we need to continue to look down from pin 1

Search for the name of pin 1, it is connected to pin 11 of J_UAT_K

Jump to the bitmap according to the name,

after determining the position, we look up the component map

In the component map, J_UAT_K is the upper antenna connector

There are volume keys, mute key, compass and other signals on the connector

In this way, all the components connected to the 5G upper antenna line are searched

When troubleshooting the weak 5G Wi-Fi signal,

we can fly a wire from the Wi-Fi antenna pin to the screw post

If the Wi-Fi signal is still poor after flying the wire, it means that the Wi-Fi chip is damaged

Ok, that's all for this video