Please help me to fix this................!

guys i want your help to fix my INVERTER MODEL: YK-S12500 E (5000W)
link: YK-S12500/E

PROBLEM


1. there is no output load installed.
2. the problem is that, when the electricity try to pass though the inverter, the protector automatically stops it.
3. the overloading LED turns ON
4. i checked all the fuses, and they are all working good.
5. i think the problem is with the capacitors.

can you help me what component should i replace...?

Your battery may be low.

I agree with mmeary,
Your battery may be low or even dead.
Have you changed the battery? Or try to charge the battery on an external charger?