Im in San Diego and I have multiple Jaboticaba trees which have fruited. Since you say your tree has fruited before, we know age or sexual maturity is not the issue.
Have you transplanted or heavily trimmed or root pruned the tree recently? Do you have yellowing leaves? What variety do you have?
Some varieties of Jaboticaba are especially sensitive to the pH of the soil. The soil in my yard was around a pH of 8 which is extremely high. If you can get the pH closer to about 6.3, your tree will be a lot happier.
If you have a Sabara or Red or Hybrid, they seem to be able to tolerate the higher pH. Several of my trees were grafted onto Sabara rootstock by Adam of Flying Fox Fruits and these trees do great, even in higher pH soils.
You should try to determine the pH of your soil. If the pH is too high, you can try to lower the pH with sulfur. This will take time, in the meantime, you can immediately lower the pH with a soil drench with phosphoric acid, don’t bring the pH down too quickly all at once, you should bring it down slowly so you don’t shock the roots.
If you have an Iron deficiency, a foliar spray with Southern Ag Citrus nutritional spray will act quickly. You may also want to drench with the appropriate chelated iron drench based on the pH of your soil.
If it’s not the pH of your soil, ensure that your trees are getting enough water. Jaboticabas love water, especially if you want them to fruit. If you are watering them enough, there’s a good chance it’s lacking nutrition of some sort.
In another post someone mentioned using Triple super phosphate(0-45-0) but I prefer to use (2-45-28) or (5-50-17) because the little bit of Nitrogen helps with fruiting and the additional Potassium helps sweeten up the fruit. I used to use these pre bloom, I would just guess and use these about 2-3 weeks before I thought something was going to bloom but I’ve since switched to 0-10-10 because I use other fertilizers which supply other macro, minor and trace elements.
Simon