No electric in my garage
No. While ground may be tied to the earth, it's also connected back to the source (distribution transformer).  Electricity doesn't flow from the transformer to the earth, it flows from the transformer back to the transformer.

Only connecting the grounding conductor to the earth, will not provide an effective ground-fault path.  So a ground-fault will not trip the breaker, as it should.

Without more information, it's difficult to tell exactly what's going on with your installation. My recommendation would be to contact a local licensed Electrician, unless you have the tools and knowledge to troubleshoot the problem yourself.