HUAWEI P40 Pro Reparaturkoffer

HUAWEI P40 Pro repair cases experience sharing.

Modell: HUAWEI P40 Pro

Announce date: March 26, 2020

Case 1. The mobile phone can be used normally, but with current leakage and consumes power quickly.

Connect the motherboard with the DC power supply and find there’s a current leakage of 200mA.

Then separate the two layers of the motherboard, and found there are two anti-static diodes (D1801 and D1803) have been burned already.

Since the two diodes are for antic static use. We’d better replace them with new ones, then assemble the motherboard to test, the phone can work normally.

Case 2. Both the Wi-Fi, Bluetooth, and camera functions failed.

This kind of issue normally is caused by the common part of Wi-Fi & Bluetooth and camera circuits.

After checking, found it’s the Camera Power IC U2101 damaged.

Replace the chip with a new one, then both the camera and Wi-Fi functions are back to normal.

 Tips: based on the repair experience, this chip damage is a common problem for the Wi-Fi and camera issues.

Case 3. No Service and Camera Function Failed After Drop Damage

This kind of issue normally is caused by the poor connection of two layers of motherboards. 

Separate the two layers of motherboards with the hot air gun and heating platform, sure enough, part of the pads between the two layers are missing. As we can see from the below picture.

So let’s fix the missing pads one by one first.

Then assemble to test, after testing, all the functions are OK.

(This is also a common issue for the P40 Pro and most two-layer structure phones.)

Case 4. Cannot Boot

Defect phenomenon: cannot boot and with current leakage once connected with the DC power.

This kind of issue is normally caused by the capacitor short, we can use the rosin inspection method to find out the shorted components.

Use the rosin inspection method, to find out the shorted component easily.

It’s the C1143 get damage

Check the schematic, it’s a filter-type capacitor. Remove it directly then phone back to normal.

(If your soldering handwork is good enough, better solder back a new capacitor with the same specification; if not, just remove it is also OK)

>> Besuch REWA AKADEMIE to learn more repair tips!