Downgrading Oracle Grid Infrastructure Using Online Abort Upgrade
If upgrade of Oracle Grid Infrastructure fails before setting the active version of Oracle Clusterware, then follow these steps to downgrade Oracle Grid Infrastructure to the earlier release.
Run this procedure to downgrade Oracle Clusterware only when the
            upgrade fails before root script runs the 
               crsctl set crs activeversion
            command on the last node. Use this procedure for downgrading Oracle Grid Infrastructure
            if there is a need to avoid downtime of the whole cluster. This procedure downgrades the
            cluster to the previous release. Because Oracle ASM and database operations are limited
            in this state, it is required to downgrade the cluster as soon as possible. Complete the
            downgrade of Oracle Grid Infrastructure as per the procedure documented in Downgrading Oracle Grid Infrastructure after Upgrade
            Fails.