New FG085 dead after about 1 minute

[helioer]

I bought a paneled kit from BangGood and built last weekend. Tested the operation connected to my lab power supply running at 15.00 V (current limit set to 800 mA). Power drain was 152 mA and all buttons seemed to have an effect on the display so I attached the panels and connected it to my scope. Something failed after about 1 minute as the display went black and power drain was maxed out. Voltage dropped to 1.28 V as the supply was running on constant current mode. Testing the circuit with my multimeter showed that power input resistance is about 6 ohm so either a short circuit or a failed active component.

When comparing the kit with Jyetech website documentation (http://www.jyetech.com/Products/085/Ass ... k_085G.pdf) I see that my kit is missing the following SMD's:
- U14
- R39
- R40
- C36
- C29
- C20
- C33
- C35
- L4
- C31
- C32
- L3
- C30
- C34
- C28
- R54
- C13
- D7
- R25
- R26
- R21

So 21 SMD's are missing. Picture with the missing parts marked is included. Most probably there is a connection between the missing parts and device failure. A lot of the components are on output part of the circuit so it may be missing output short circuit protection (always a possibility when connecting devices together with test leads).

[jye1]

All the SMDs circled were not populated intentionally. On early productions U14, R39, R40, D7, R21, R25, and R26 were installed as provision for possible future upgrade. Later due to running out of flash space we gave up the plan of upgrade. As a result these parts were removed from BOM to low cost a bit. They had never been functional. They should not relate to the issue you encountered.