This morning I see that the rac services was not available for one of the instances of the database in RAC, simply start with srvctl start service and start without problems.
In the crs log is not something failed, where else I can look for the cause of the problem?
NOTE: The database instance never restart.
If the service was offline then you can find the failure message in crsd log, however, if you do not see anything logged then you should check the target of the resource, was the same "OFFLINE". If so then probably someone would have stopped the service
Else, you can also check in the database instance alert log, around what time was the "alter system set service" statement last got executed, you can get some idea from there as well
Vandana - Oracle