Mondeo 2.0 diesel titanium x not starting

[Rod2010]

My mondeo has started having problems starting, when pressing the start button it clicks as if there's a flat battery but comes up on the screen as "Engine malfunction" I'm not convinced it's the battery as tried it about 2 hours later and it started but this is the 4th time it has happened, got mates to push car and jumped started and works fine, now stuck on drive and can't start again, any ideas fellas