If your LG cell phone stays in the logo, constantly rebooting into a « bootloop «, it is possible that it is due to a software failure, something that, as we have seen before, is easily solved after restoring the factory settings from the recovery. However, it is also quite likely to be a physical or hardware failure, especially if it is an LG G4, Nexus 5X and even some later models.
The problem is that these LG cell phone models suffer from loose contacts or loss of contact between the components due to poor soldering. This was recognized by the company itself.
At the time and in some parts of the world LG offered to repair this factory flaw, which could not be fixed using software “tricks”. However, the period for you to request this repair has expired a long time ago, so you will have to fix it yourself.
Since the problem is unstable solders, it is recommended to do a reballing or soldering of the electronic board in a professional technical service. Although there is a homemade solution, it is risky and may not be worth it. Proceed under your responsibility.
Homemade solution
To verify that the constant restart of the mobile is indeed due to a loss of contact between components, put the device in the freezer for around 6 or 7 minutes , in a tight plastic bag (this is vital). If after that the device starts up normally then it may be the welds.
Heat the electronic board in an oven
Software engineer Alexander Gee deduced that the fault with his Nexus 5 was in the RAM contacts. He solved it by putting the electronic board on aluminum foil, the latter touching the contacts, on a flat ceramic utensil, in the oven for 6 and a half minutes , at a temperature of 195 degrees Celsius . After waiting for it to cool down , he put the device back together.
At least four other people on this blog commented that the method worked , although each used their own variant. In addition to the oven they used an iron for 15 minutes, or a heat gun for 20 seconds.
The disadvantage of this procedure, known as reflow soldering or reflow , is that it can damage the circuit and even the electronics if done incorrectly. Also sometimes it lasts no more than a few hours. A professional medium-term solution is to do a Reballing or Rework , which is a complete solution with specialized machines.
More information : «Dev With Alex» (bit.ly/2QE3Alq)