Rangers slumped 3-0 at Sheffield Wednesday on Tuesday night, their fifth defeat in eight matches which has seen them slip way off the promotion pace.
Unhappy supporters took to Twitter to vent their anger, but Fernandes responded by insisting he is fully behind Redknapp and his injury-hit squad as they rebuild after last season's relegation.
"QPR fans. Being negative is so so wrong. We learn and we move. There are a few games left. So much to look forward to," he replied.
"Who likes to lose. But come on guys. Stop blaming everyone. Let's stick together and do our best to get up.
"The person who should be most depressed is me. But I am not. We are building and building. And we make mistakes and we learn.
"In troubled times now is the time to stand behind your club manager and players.
"I stand by my players. Full stop and my manager.
"Look a leader stands behind his troops. Now is the time we should rally round Harry and the players.
"No one wants to lose. Last season was a disaster. Full stop. We have stopped the rot. Every year we will rebuild."