diff --git a/lib/datasource.js b/lib/datasource.js
index 05295857..8b33d0a5 100644
--- a/lib/datasource.js
+++ b/lib/datasource.js
@@ -2151,7 +2151,7 @@ DataSource.prototype.ping = function(cb) {
     self.discoverModelProperties('dummy', {}, cb);
   } else {
     process.nextTick(function() {
-      var err = self.connected ? null : 'Not connected';
+      var err = self.connected ? null : new Error('Not connected');
       cb(err);
     });
   }