When your Samsung Android mobile was bricked (soft), reflash the rom is the only option to recover the mobile. To reflash with new rom, you have to boot your mobile in download mode using combination of key (Mostly Volume Down + Power + Home). Some times, the key combination will not work out. Helpless! USB JIG is the solution. You can buy a USB JIG or Do-it-Yourself.
This is only for an idea. You make it at your own risk or get expert’s advice. I am no way responsible for any loss / damage caused while making or using this idea.
1) MicroUSB Male Pin,
2) 301 Kilo Ohms Resistors or 3 Nos. of 100K + 1 No. of 1K
3) Knife, Soldering Iron, tweezer will simplify your work.
MicroUSB Male pin and Resistors will boot your Mobile in Downloading Mode.
Step 1: Schematic
Connecting 301K resistor between Pin No. of 4 and 5 is the USB JIG which force your mobile to boot in Downloading Mode. The schematic shown in Fig (1).
Step 2: Procure MicroUSB Pin
Buy a Micro USB Pin or Buy a charger adapter which cost Rs.10/- Second one may be useful to house the resistor in it. There are two type of adapters are available in the market as shown in Fig. (2) & (3). Both are fine. The problem is number of Pins. Check the number of Pins before buy. Because 4th Pin will not be available in some of the charger adapters which is not useful for us. Compare them in Fig. (4). Select adapter which has 5 Pins.
Step 3: Prepare the Micro USB Pin
Bisect the case using Knife or Tweezer (Fig.(5)). There will be two pins, one is Micro USB male and Nokia charger Female or others as you procured. Trim the wires using Soldering Iron and separate the Micro USB Pin (Fig. (6)). Only Pin No. 5 and 4 alone to be utilized. So, remove the other pins except 4, 5 using tweezer or Needle to avoid any short circuit. Be causious as Pin No. 4 or 5 may come along with the other pins (Fig.(7) & (8)).
Step 4: Wiring
The Pins are so tiny. So, insert two thin pins in the chamber of Pin No. 4, 5 tightly alongwith the exiting one, so we can easily solder the resistors (Fig.(9)). The JIG may works fine from 300K to 400K, typical value is 301K. Solder three 100K Resistors and one 1K Resistors one by one (Fig.(10) &(11)). Bend the Resistors as shown in picture as shown in Fig.(12) so we can house in the case.
Step 5: Housing the Resistor
Solder the resistor series between Pin No. 4 & 5 of MicroUSB Pin as shown in Fig (13), Place them in the case (Fig.(14)) close it tightly Fig.(15)). Wrap it with sticker and write any marks (Fig.(16) to avoid miss handling by some others. Now the USB JIG is ready.
Step 6: Prepare Your Mobile
Take the phone and remove the battery and wait for a minute. Then Insert the batter to your mobile and do not press any buttons.
Step 7: Test Your Mobile
Simply insert the USB JIG into the USB Port/ Charger pin and keep it for some seconds. Congrats, your mobile started in ‘Downloading mode’. When you see the Downloading screen remove the USB JIG immediately and plug the USB Data cable with computer and install new firmware etc., using ODIN or some other tools you familiar.
Step 8: Final
If your mobile has not any response even after 10 seconds, recheck the wiring and do the steps again from 17. Now, it will work out otherwise, your mobile was hard bricked and RIFF BOX - JTAG method may help you.
All the Best.