| Symptom | Most Likely Cause | Fix | | :--- | :--- | :--- | | No output, VIN present | EN pin floating or pulled low | Pull EN high with a 100k resistor to VIN | | Output voltage too low (e.g., 2V instead of 5V) | Current limit triggered by shorted load or bad inductor | Check output capacitor for short; replace inductor | | Chip gets hot at low load | Fake or counterfeit MTK 1014 (often a linear regulator relabeled) | Source from authorized distributor | | Output oscillating or whining | Improper compensation network (COMP pin) | Adjust RC values per datasheet; add 10pF across FB resistor | | No battery charging | CHRG pin stuck high | Check battery voltage; <2.5V may indicate deep discharge protection |
: 18.5-inch 4140 steel, chrome-lined, and threaded for Benelli/Mobil-pattern chokes. mtk 1014
