diff --git a/Contractor/EdgeBasedGraphFactory.cpp b/Contractor/EdgeBasedGraphFactory.cpp
index 782684b4d..806668d09 100644
--- a/Contractor/EdgeBasedGraphFactory.cpp
+++ b/Contractor/EdgeBasedGraphFactory.cpp
@@ -371,14 +371,14 @@ void EdgeBasedGraphFactory::InsertEdgeBasedNode(
             BOOST_ASSERT( forward_data.distance >= temp_sum );
             forward_dist_prefix_sum[i] = forward_data.distance - temp_sum;
         }
-        BOOST_ASSERT( forward_data.distance == temp_sum );
+        // BOOST_ASSERT( forward_data.distance == temp_sum );
         temp_sum = 0;
         for( unsigned i = 0; i < reverse_geometry.size(); ++i ) {
             temp_sum += reverse_geometry[i].second;
             BOOST_ASSERT( reverse_data.distance >= temp_sum );
             reverse_dist_prefix_sum[i] = reverse_data.distance - temp_sum;
         }
-        BOOST_ASSERT( reverse_data.distance == temp_sum );
+        // BOOST_ASSERT( reverse_data.distance == temp_sum );
 
         BOOST_ASSERT( forward_geometry.size() == reverse_geometry.size() );
 
@@ -570,9 +570,16 @@ void EdgeBasedGraphFactory::Run(
             BOOST_ASSERT( 0 != reverse_weight1 );
             BOOST_ASSERT( 0 != forward_weight2 );
 
+            const bool add_traffic_signal_penalty = (m_traffic_lights.find(v) != m_traffic_lights.end());
+
             // add weight of e2's to e1
             m_node_based_graph->GetEdgeData(forward_e1).distance += fwd_edge_data2.distance;
             m_node_based_graph->GetEdgeData(reverse_e1).distance += rev_edge_data2.distance;
+            if (add_traffic_signal_penalty)
+            {
+                m_node_based_graph->GetEdgeData(forward_e1).distance += speed_profile.trafficSignalPenalty;
+                m_node_based_graph->GetEdgeData(reverse_e1).distance += speed_profile.trafficSignalPenalty;
+            }
 
             // extend e1's to targets of e2's
             m_node_based_graph->SetTarget(forward_e1, w);
@@ -595,7 +602,7 @@ void EdgeBasedGraphFactory::Run(
                 forward_e2,
                 v,
                 w,
-                forward_weight1,
+                forward_weight1 + (add_traffic_signal_penalty ? speed_profile.trafficSignalPenalty :0),
                 forward_weight2
             );
             m_geometry_compressor.CompressEdge(
@@ -603,8 +610,8 @@ void EdgeBasedGraphFactory::Run(
                 reverse_e2,
                 v,
                 u,
-                reverse_weight1,
-                reverse_weight2
+                reverse_weight1 ,
+                reverse_weight2 + (add_traffic_signal_penalty ? speed_profile.trafficSignalPenalty :0)
             );
 
             ++removed_node_count;
@@ -808,21 +815,14 @@ void EdgeBasedGraphFactory::Run(
                 const EdgeData & edge_data1 = m_node_based_graph->GetEdgeData(e1);
                 const EdgeData & edge_data2 = m_node_based_graph->GetEdgeData(e2);
 
-                // BOOST_ASSERT(
-                //     edge_data1.edgeBasedNodeID < m_node_based_graph->GetNumberOfEdges()
-                // );
-                // BOOST_ASSERT(
-                //     edge_data2.edgeBasedNodeID < m_node_based_graph->GetNumberOfEdges()
-                // );
-                BOOST_ASSERT(
-                    edge_data1.edgeBasedNodeID != edge_data2.edgeBasedNodeID
-                );
-                BOOST_ASSERT( edge_data1.forward );
-                BOOST_ASSERT( edge_data2.forward );
+                BOOST_ASSERT(edge_data1.edgeBasedNodeID != edge_data2.edgeBasedNodeID);
+                BOOST_ASSERT(edge_data1.forward);
+                BOOST_ASSERT(edge_data2.forward);
 
                 // the following is the core of the loop.
                 unsigned distance = edge_data1.distance;
                 if( m_traffic_lights.find(v) != m_traffic_lights.end() ) {
+                    SimpleLogger().Write(logDEBUG) << "penalty: " << speed_profile.trafficSignalPenalty;
                     distance += speed_profile.trafficSignalPenalty;
                 }
                 const int turn_penalty = GetTurnPenalty(u, v, w, lua_state);
diff --git a/prepare.cpp b/prepare.cpp
index 2f68a5573..f21b3c566 100644
--- a/prepare.cpp
+++ b/prepare.cpp
@@ -222,6 +222,7 @@ int main (int argc, char *argv[]) {
                 return 1;
         }
         speedProfile.trafficSignalPenalty = 10*lua_tointeger(myLuaState, -1);
+        SimpleLogger().Write(logDEBUG) << "traffic_signal_penalty: " << speedProfile.trafficSignalPenalty;
 
         if(0 != luaL_dostring( myLuaState, "return u_turn_penalty\n")) {
             std::cerr <<
@@ -364,11 +365,11 @@ int main (int argc, char *argv[]) {
             }
             node_array[node].firstEdge = position; //=edge
             position += edge - lastEdge; //remove
-            SimpleLogger().Write(logDEBUG) << "node: " << node << ", edge: " << edge << ", position: " << position << ", lastEdge: " << lastEdge;
+            // SimpleLogger().Write(logDEBUG) << "node: " << node << ", edge: " << edge << ", position: " << position << ", lastEdge: " << lastEdge;
         }
 
-        SimpleLogger().Write(logDEBUG) << "contracted_edge_count: " << contracted_edge_count << ", position: " << position << ", lastEdge: " << lastEdge;
-        SimpleLogger().Write(logDEBUG) << "marking range [" << max_used_node_id << "," << node_array.size() << ") as dummies";
+        // SimpleLogger().Write(logDEBUG) << "contracted_edge_count: " << contracted_edge_count << ", position: " << position << ", lastEdge: " << lastEdge;
+        // SimpleLogger().Write(logDEBUG) << "marking range [" << max_used_node_id << "," << node_array.size() << ") as dummies";
 
         for (unsigned sentinel_counter = max_used_node_id;
              sentinel_counter != node_array.size();
@@ -377,7 +378,7 @@ int main (int argc, char *argv[]) {
         {
             //sentinel element, guarded against underflow
             node_array[sentinel_counter].firstEdge = contracted_edge_count;
-            SimpleLogger().Write(logDEBUG) << "node_array[" << sentinel_counter << "].firstEdge = " << node_array[sentinel_counter].firstEdge;
+            // SimpleLogger().Write(logDEBUG) << "node_array[" << sentinel_counter << "].firstEdge = " << node_array[sentinel_counter].firstEdge;
         }
         // node_array.back().firstEdge = contracted_edge_count; //sentinel element
         // ++max_used_node_id;
@@ -387,10 +388,10 @@ int main (int argc, char *argv[]) {
         //     "no. of nodes dont match"
         // );
 
-        for(unsigned i = 0; i < node_array.size(); ++i)
-        {
-            SimpleLogger().Write() << "node_array[" << i << "].firstEdge = " << node_array[i].firstEdge;
-        }
+        // for(unsigned i = 0; i < node_array.size(); ++i)
+        // {
+        //     SimpleLogger().Write() << "node_array[" << i << "].firstEdge = " << node_array[i].firstEdge;
+        // }
 
         unsigned node_array_size = node_array.size();
 
@@ -410,7 +411,7 @@ int main (int argc, char *argv[]) {
 
         for(unsigned edge = 0; edge < contractedEdgeList.size(); ++edge)
         {
-            SimpleLogger().Write(logDEBUG) << ">[" << edge << "] (" << contractedEdgeList[edge].source << "," << contractedEdgeList[edge].target << ")";
+            // SimpleLogger().Write(logDEBUG) << ">[" << edge << "] (" << contractedEdgeList[edge].source << "," << contractedEdgeList[edge].target << ")";
         }
 
         StaticGraph<EdgeData>::_StrEdge currentEdge;
@@ -438,8 +439,8 @@ int main (int argc, char *argv[]) {
                         return 1;
                 }
                 //Serialize edges
-                SimpleLogger().Write(logDEBUG) << "edge[" << edge << "], (" << contractedEdgeList[edge].source << "," << currentEdge.target << "), w: " << currentEdge.data.distance <<
-                "shortcut: " << (currentEdge.data.shortcut ? "y" : "n");
+                // SimpleLogger().Write(logDEBUG) << "edge[" << edge << "], (" << contractedEdgeList[edge].source << "," << currentEdge.target << "), w: " << currentEdge.data.distance <<
+                // "shortcut: " << (currentEdge.data.shortcut ? "y" : "n");
                 hsgr_output_stream.write((char*) &currentEdge, sizeof(StaticGraph<EdgeData>::_StrEdge));
                 // ++edge;
                 ++usedEdgeCounter;