No, you can't if the engine overheats are risking to damage the head gasket. And if it happens it costs depending on damage from $600-700 to $3000 to fix.
The 2012 Toyota Yaris has an inline 4 engine.
The 2007 Toyota Yaris has an inline 4 engine.
The 2008 Toyota Yaris has an inline 4 engine.
The 2010 Toyota Yaris has an inline 4 engine.
The 2014 Toyota Yaris has an inline 4 engine.
The 2011 Toyota Yaris has an inline 4 engine.
The 2013 Toyota Yaris has an inline 4 engine.
The 2009 Toyota Yaris has an inline 4 engine.
The 2014 Toyota Yaris has a 1.5 L base engine size.
The 2013 Toyota Yaris has a 1.5 L base engine size.
The 2011 Toyota Yaris has a 1.5 L base engine size.
The 2012 Toyota Yaris has a 1.5 L base engine size.