Why does Samsung I458 always flash orange when charging?

That light is actually a red LED and a green LED in a plastic bag.

When charging, the control circuit controls the red LED to emit light, and the green LED goes out, so it displays red, and when fully charged, it displays green.

In fact, if you look carefully, when the charge is almost full, the light will change from red to green. When it turns green, it means that the charging current is already very small.

However, if the battery performance is poor, there is leakage or there is something wrong with the control circuit, then both lights will light up and display orange.

Flicker indicates current fluctuation, that is, the charging voltage is unstable, which is due to the reduction or failure of the filter capacitor capacity.