Remove the battery for 5 seconds, then reinsert it (do not turn the phone on).
Understanding the hardware limits helps you choose the right firmware. 800 MHz Qualcomm Snapdragon S1 (MSM7225A) RAM: 384 MB Storage: 1 GB internal storage (system and app space) Display: 3.2 inches, 240 x 320 pixels (QVGA) Original OS: Android 2.3.6 Gingerbread Stock Firmware vs. Custom ROMs Firmware LG E400 Optimus L3
Resolves instances where the phone gets stuck on the LG logo. Remove the battery for 5 seconds, then reinsert