5G Smartphone Short Circuit Repair – New Diagnosis Method
In this tutorial we will learn a new method to detect and remove short circuits in modern 5G smartphones. Short circuit problems are very common in mobile repairing and proper diagnosis is required before replacing any component.
Step 1 – Identify Short Circuit Using DC Power Supply
First connect the phone motherboard to a DC Power Supply or Smart Charger.
- If the board draws high current immediately → Main line short
- If current is normal → No direct short circuit
Most short circuits appear on the BPPH / VBAT main power line.
Step 2 – Inspect Main Power Sections
After confirming a short circuit, inspect important sections of the motherboard:
- Power IC (PMIC)
- Charging IC
- CPU Area
- Main Power Capacitors
These components are connected directly to the main battery line and often cause short circuits.
Step 3 – Check Capacitors in Diode Mode
Use a multimeter in diode mode to test capacitors connected to the power line.
- Normal capacitor → shows diode reading
- Short capacitor → shows 0 or very low reading
Step 4 – Voltage Injection Technique
If the faulty component is difficult to identify, use the Voltage Injection Method.
Inject low voltage through a DC power supply into the shorted line. The faulty component will start heating slightly.
Using thermal detection or finger touch you can identify the hot component.
Common Components That Cause Short Circuits
- Power IC (PMIC)
- Charging IC
- RF IC
- Capacitors near CPU
- Buck converter circuits
Step 5 – Remove the Faulty Component
Once the faulty component is identified, remove or replace it carefully.
After removal, check the board again using a multimeter.
- If diode readings become normal → Short removed
- If short still present → continue diagnosis
Final Result
After removing the faulty component, the motherboard should return to normal condition and the phone should power on successfully.