Guidance on seemingly failed electronic components on EB3A unit

Hello
Trying to make a long story short: EB3A unit has failed. Only powers up when AC or solar input is supplied and shuts down after less than 10 seconds. Pressing the power buttons does nothing, it has cut off not gone into sleep/power conserve mode.
Since the unit is located outside the USA it is almost the cost of a new unit to just ship it back for the warranty to be honored.
Since it is to be discarded I opened it up and discovered that a part of the circuit board on the inverter looks burnt. Can you tell me what those damaged components are? As in the exact part numbers so that an electronics repair technician might be able to replace them.

Like I said, there is no way for Bluetti to do the repairs so I would appreciate at least a chance of getting the unit functional again.

The two burned components are SMD resistors.
The nearest component marked DB is probably a DIAC or a TVS.
If you have the appropriate tools, you could clean the burned area with isopropyl alcohol, remove the burned component from the PCB with a hot air gun and better check if the copper traces are still intact.

Hi @Raj1 , We would like to know which country or region you are currently in. We need to determine if your EB3A can still provide AC output. If it can, we can try pushing a new firmware to resolve the issue. If it cannot, then it’s likely a hardware fault that requires repair.

If you want to repair your EB3A, it’s difficult to diagnose the problem just from the photo, as there could be other underlying issues that are not visible. There might also be some faulty MOS tubes that we cannot identify from the pictures.

Therefore, simply providing the part number may not be helpful. The best solution would be to replace the mainboard. We suggest sending the PCBA board to a repair center or checking if we have a local agent who can provide a PCBA board.

Thanks to @ndwr for the assistance and troubleshooting.

I’m in the Caribbean.
I had posted this issue previously and it was realized that the unit only supplies AC output for the time it stays on, which was about 5 seconds.
From the circuit board it clearly is a hardware fault.

I do appreciate that there might be other damage arising from the initial failure of the resistors.

Is that PCBA board available for purchase anywhere like Amazon or Ebay?
Thank you and ndwr for your replies.

R46 & R163 is resistor 200 Om P>0.5W (recommend 1W)
DB1 is Bridge Rectifiers Urrm=1000V If(av)=3А min (For example YBS3010)

Hi @Raj1, If you confirm that your EB3A can still output AC, we can attempt a firmware upgrade and bypass the resistor, which might help achieve normal operation.
Please provide your EB3A’s SN number and current firmware version, which you can find in the app. We will try to resolve the issue.
Additionally, we do not currently sell PCBA boards. We suggest checking with eBay second-hand sellers to see if they have any in stock.

@Rusja, thank you for the detailed info. Unfortunately there are no electronic repair companies I can find locally.

@BLUETTI_CARE unfortunately the unit would only power on when input was supplied and after 5 seconds at most, it would cut off. Due to the length of time it has remained without power, the battery voltage has fallen below 12V which I believe is required to keep the BMS operational.

This looks like a lost cause. Thank you all for your feedback.

Thank you for letting us know, I am sorry we failed to help you on this matter.