iPhone Wi-Fi circuit repairing

This video mainly explains how to find the Wi-Fi 2.4G and 5G antenna signals of iPhone 12 and 12Pro

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

When checking the maps, first open the component map, circuit diagram, and bitmap of the iPhone 12 and 12 Pro

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, 2G_C0_ANT represents the 2.4G upper antenna

2G_C1_ANT represents 2.4G lower antenna

5G_C0_ANT represents the 5G upper antenna

5G_C1_ANT represents the 5G 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

When we check the weak Wi-Fi signal,

we only need to find the signal of the upper antenna, and there is no need to search for the lower antenna

If we find that the 5G signal is relatively poor, we need to find the 5G lines

Let's find the 2.4G upper antenna line first

Pin 28 of the Wi-Fi chip is the 5G upper antenna line

After the line comes out, it is connected to the resistor R233_W,

and connected to FL_ISG_U_W

This component is a filter

After passing through the filter, the line is connected to the resistor R201_W

After passing through the resistor, we search for the signal name at 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

Continue to search down

The signal is connected to the resistor R363_W

And connected to U_5G_U_W after passing through the resistor

The chip is an antenna filter

The upper pin is the power supply pin,

and the lower pin is the control or detection pin

When looking for the line, we need to continue to look down from the ANT pin of the chip

Pin 26 of the chip is the antenna pin, ANT

After the 26 pin comes out,

it is connected to the resistor R365_W,

and after passing through the resistor, it is connected to the filter DPLXR_U_W

After passing through the filter, the signal is connected to the resistor R301_W

After passing through the resistor, the signal is connected to pin 22 of JUAT1

Jump to the bitmap according to the name,

after determining the position, we look up the component map

We can see that JUAT1 is the upper antenna connection seat in the component map

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 directly fly a wire to the 2.4G upper antenna pin of the Wi-Fi chip

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