diff --git a/cnexp_array/neuron/leonhard.cpp b/cnexp_array/neuron/leonhard.cpp
index dc66bc0..066c96a 100644
--- a/cnexp_array/neuron/leonhard.cpp
+++ b/cnexp_array/neuron/leonhard.cpp
@@ -103,6 +103,7 @@ namespace neuron {
     struct leonhard_NodeData  {
         int const * nodeindices;
         double const * node_voltages;
+        double * node_diagonal;
         double * node_rhs;
         int nodecount;
     };
@@ -125,6 +126,7 @@ namespace neuron {
         return leonhard_NodeData {
             _ml_arg.nodeindices,
             _nt.node_voltage_storage(),
+            _nt.node_d_storage(),
             _nt.node_rhs_storage(),
             _ml_arg.nodecount
         };
@@ -208,7 +210,17 @@ namespace neuron {
 
 
     /** nrn_jacob function */
-    static void nrn_jacob_leonhard(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {}
+    static void nrn_jacob_leonhard(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {
+        _nrn_mechanism_cache_range _lmr{_sorted_token, *_nt, *_ml_arg, _type};
+        auto inst = make_instance_leonhard(_lmr);
+        auto node_data = make_node_data_leonhard(*_nt, *_ml_arg);
+        auto nodecount = _ml_arg->nodecount;
+        for (int id = 0; id < nodecount; id++) {
+            // set conductances properly
+            int node_id = node_data.nodeindices[id];
+            node_data.node_diagonal[node_id] += inst.g_unused[id];
+        }
+    }
 
 
     static void _initlists() {
diff --git a/cnexp_scalar/neuron/leonhard.cpp b/cnexp_scalar/neuron/leonhard.cpp
index 9d82dc2..c3048b2 100644
--- a/cnexp_scalar/neuron/leonhard.cpp
+++ b/cnexp_scalar/neuron/leonhard.cpp
@@ -97,6 +97,7 @@ namespace neuron {
     struct leonhard_NodeData  {
         int const * nodeindices;
         double const * node_voltages;
+        double * node_diagonal;
         double * node_rhs;
         int nodecount;
     };
@@ -116,6 +117,7 @@ namespace neuron {
         return leonhard_NodeData {
             _ml_arg.nodeindices,
             _nt.node_voltage_storage(),
+            _nt.node_d_storage(),
             _nt.node_rhs_storage(),
             _ml_arg.nodecount
         };
@@ -194,7 +196,17 @@ namespace neuron {
 
 
     /** nrn_jacob function */
-    static void nrn_jacob_leonhard(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {}
+    static void nrn_jacob_leonhard(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {
+        _nrn_mechanism_cache_range _lmr{_sorted_token, *_nt, *_ml_arg, _type};
+        auto inst = make_instance_leonhard(_lmr);
+        auto node_data = make_node_data_leonhard(*_nt, *_ml_arg);
+        auto nodecount = _ml_arg->nodecount;
+        for (int id = 0; id < nodecount; id++) {
+            // set conductances properly
+            int node_id = node_data.nodeindices[id];
+            node_data.node_diagonal[node_id] += inst.g_unused[id];
+        }
+    }
 
 
     static void _initlists() {
diff --git a/func_proc/neuron/func_proc.cpp b/func_proc/neuron/func_proc.cpp
index b15e8d0..08e19ab 100644
--- a/func_proc/neuron/func_proc.cpp
+++ b/func_proc/neuron/func_proc.cpp
@@ -93,6 +93,7 @@ namespace neuron {
     struct test_func_proc_NodeData  {
         int const * nodeindices;
         double const * node_voltages;
+        double * node_diagonal;
         double * node_rhs;
         int nodecount;
     };
@@ -110,6 +111,7 @@ namespace neuron {
         return test_func_proc_NodeData {
             _ml_arg.nodeindices,
             _nt.node_voltage_storage(),
+            _nt.node_d_storage(),
             _nt.node_rhs_storage(),
             _ml_arg.nodecount
         };
@@ -367,7 +369,14 @@ namespace neuron {
 
 
     /** nrn_jacob function */
-    static void nrn_jacob_test_func_proc(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {}
+    static void nrn_jacob_test_func_proc(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {
+        _nrn_mechanism_cache_range _lmr{_sorted_token, *_nt, *_ml_arg, _type};
+        auto inst = make_instance_test_func_proc(_lmr);
+        auto node_data = make_node_data_test_func_proc(*_nt, *_ml_arg);
+        auto nodecount = _ml_arg->nodecount;
+        for (int id = 0; id < nodecount; id++) {
+        }
+    }
 
 
     static void _initlists() {
diff --git a/func_proc_pnt/neuron/func_proc_pnt.cpp b/func_proc_pnt/neuron/func_proc_pnt.cpp
index 5ef3ee3..9ef393b 100644
--- a/func_proc_pnt/neuron/func_proc_pnt.cpp
+++ b/func_proc_pnt/neuron/func_proc_pnt.cpp
@@ -92,6 +92,7 @@ namespace neuron {
     struct test_func_proc_pnt_NodeData  {
         int const * nodeindices;
         double const * node_voltages;
+        double * node_diagonal;
         double * node_rhs;
         int nodecount;
     };
@@ -110,6 +111,7 @@ namespace neuron {
         return test_func_proc_pnt_NodeData {
             _ml_arg.nodeindices,
             _nt.node_voltage_storage(),
+            _nt.node_d_storage(),
             _nt.node_rhs_storage(),
             _ml_arg.nodecount
         };
@@ -293,7 +295,14 @@ namespace neuron {
 
 
     /** nrn_jacob function */
-    static void nrn_jacob_test_func_proc_pnt(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {}
+    static void nrn_jacob_test_func_proc_pnt(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {
+        _nrn_mechanism_cache_range _lmr{_sorted_token, *_nt, *_ml_arg, _type};
+        auto inst = make_instance_test_func_proc_pnt(_lmr);
+        auto node_data = make_node_data_test_func_proc_pnt(*_nt, *_ml_arg);
+        auto nodecount = _ml_arg->nodecount;
+        for (int id = 0; id < nodecount; id++) {
+        }
+    }
 
 
     static void _initlists() {
diff --git a/global_breakpoint/neuron/leonhard.cpp b/global_breakpoint/neuron/leonhard.cpp
index 6971917..55c7ed2 100644
--- a/global_breakpoint/neuron/leonhard.cpp
+++ b/global_breakpoint/neuron/leonhard.cpp
@@ -97,6 +97,7 @@ namespace neuron {
     struct leonhard_NodeData  {
         int const * nodeindices;
         double const * node_voltages;
+        double * node_diagonal;
         double * node_rhs;
         int nodecount;
     };
@@ -116,6 +117,7 @@ namespace neuron {
         return leonhard_NodeData {
             _ml_arg.nodeindices,
             _nt.node_voltage_storage(),
+            _nt.node_d_storage(),
             _nt.node_rhs_storage(),
             _ml_arg.nodecount
         };
@@ -195,7 +197,17 @@ namespace neuron {
 
 
     /** nrn_jacob function */
-    static void nrn_jacob_leonhard(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {}
+    static void nrn_jacob_leonhard(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {
+        _nrn_mechanism_cache_range _lmr{_sorted_token, *_nt, *_ml_arg, _type};
+        auto inst = make_instance_leonhard(_lmr);
+        auto node_data = make_node_data_leonhard(*_nt, *_ml_arg);
+        auto nodecount = _ml_arg->nodecount;
+        for (int id = 0; id < nodecount; id++) {
+            // set conductances properly
+            int node_id = node_data.nodeindices[id];
+            node_data.node_diagonal[node_id] += inst.g_unused[id];
+        }
+    }
 
 
     static void _initlists() {
diff --git a/nonspecific_current/neuron/leonhard.cpp b/nonspecific_current/neuron/leonhard.cpp
index 9042934..f52e8a3 100644
--- a/nonspecific_current/neuron/leonhard.cpp
+++ b/nonspecific_current/neuron/leonhard.cpp
@@ -94,6 +94,7 @@ namespace neuron {
     struct leonhard_NodeData  {
         int const * nodeindices;
         double const * node_voltages;
+        double * node_diagonal;
         double * node_rhs;
         int nodecount;
     };
@@ -112,6 +113,7 @@ namespace neuron {
         return leonhard_NodeData {
             _ml_arg.nodeindices,
             _nt.node_voltage_storage(),
+            _nt.node_d_storage(),
             _nt.node_rhs_storage(),
             _ml_arg.nodecount
         };
@@ -199,6 +201,8 @@ namespace neuron {
             double rhs = I0;
             double g = (I1-I0)/0.001;
             node_data.node_rhs[node_id] -= rhs;
+            // remember the conductances so we can set them later
+            inst.g_unused[id] = g;
         }
     }
 
@@ -214,7 +218,17 @@ namespace neuron {
 
 
     /** nrn_jacob function */
-    static void nrn_jacob_leonhard(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {}
+    static void nrn_jacob_leonhard(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {
+        _nrn_mechanism_cache_range _lmr{_sorted_token, *_nt, *_ml_arg, _type};
+        auto inst = make_instance_leonhard(_lmr);
+        auto node_data = make_node_data_leonhard(*_nt, *_ml_arg);
+        auto nodecount = _ml_arg->nodecount;
+        for (int id = 0; id < nodecount; id++) {
+            // set conductances properly
+            int node_id = node_data.nodeindices[id];
+            node_data.node_diagonal[node_id] += inst.g_unused[id];
+        }
+    }
 
 
     static void _initlists() {
diff --git a/parameter/neuron/neuron_variables.cpp b/parameter/neuron/neuron_variables.cpp
index de17ba9..55eb84b 100644
--- a/parameter/neuron/neuron_variables.cpp
+++ b/parameter/neuron/neuron_variables.cpp
@@ -96,6 +96,7 @@ namespace neuron {
     struct NeuronVariables_NodeData  {
         int const * nodeindices;
         double const * node_voltages;
+        double * node_diagonal;
         double * node_rhs;
         int nodecount;
     };
@@ -115,6 +116,7 @@ namespace neuron {
         return NeuronVariables_NodeData {
             _ml_arg.nodeindices,
             _nt.node_voltage_storage(),
+            _nt.node_d_storage(),
             _nt.node_rhs_storage(),
             _ml_arg.nodecount
         };
@@ -192,7 +194,17 @@ namespace neuron {
 
 
     /** nrn_jacob function */
-    static void nrn_jacob_NeuronVariables(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {}
+    static void nrn_jacob_NeuronVariables(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {
+        _nrn_mechanism_cache_range _lmr{_sorted_token, *_nt, *_ml_arg, _type};
+        auto inst = make_instance_NeuronVariables(_lmr);
+        auto node_data = make_node_data_NeuronVariables(*_nt, *_ml_arg);
+        auto nodecount = _ml_arg->nodecount;
+        for (int id = 0; id < nodecount; id++) {
+            // set conductances properly
+            int node_id = node_data.nodeindices[id];
+            node_data.node_diagonal[node_id] += inst.g_unused[id];
+        }
+    }
 
 
     static void _initlists() {
diff --git a/parameter/neuron/test_parameter.cpp b/parameter/neuron/test_parameter.cpp
index b7690f9..fe11229 100644
--- a/parameter/neuron/test_parameter.cpp
+++ b/parameter/neuron/test_parameter.cpp
@@ -92,6 +92,7 @@ namespace neuron {
     struct test_parameter_NodeData  {
         int const * nodeindices;
         double const * node_voltages;
+        double * node_diagonal;
         double * node_rhs;
         int nodecount;
     };
@@ -110,6 +111,7 @@ namespace neuron {
         return test_parameter_NodeData {
             _ml_arg.nodeindices,
             _nt.node_voltage_storage(),
+            _nt.node_d_storage(),
             _nt.node_rhs_storage(),
             _ml_arg.nodecount
         };
@@ -202,7 +204,14 @@ namespace neuron {
 
 
     /** nrn_jacob function */
-    static void nrn_jacob_test_parameter(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {}
+    static void nrn_jacob_test_parameter(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {
+        _nrn_mechanism_cache_range _lmr{_sorted_token, *_nt, *_ml_arg, _type};
+        auto inst = make_instance_test_parameter(_lmr);
+        auto node_data = make_node_data_test_parameter(*_nt, *_ml_arg);
+        auto nodecount = _ml_arg->nodecount;
+        for (int id = 0; id < nodecount; id++) {
+        }
+    }
 
 
     static void _initlists() {
diff --git a/point_process/neuron/test_pp.cpp b/point_process/neuron/test_pp.cpp
index f4d4b48..fc6a849 100644
--- a/point_process/neuron/test_pp.cpp
+++ b/point_process/neuron/test_pp.cpp
@@ -90,6 +90,7 @@ namespace neuron {
     struct test_pp_NodeData  {
         int const * nodeindices;
         double const * node_voltages;
+        double * node_diagonal;
         double * node_rhs;
         int nodecount;
     };
@@ -107,6 +108,7 @@ namespace neuron {
         return test_pp_NodeData {
             _ml_arg.nodeindices,
             _nt.node_voltage_storage(),
+            _nt.node_d_storage(),
             _nt.node_rhs_storage(),
             _ml_arg.nodecount
         };
@@ -198,7 +200,14 @@ namespace neuron {
 
 
     /** nrn_jacob function */
-    static void nrn_jacob_test_pp(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {}
+    static void nrn_jacob_test_pp(_nrn_model_sorted_token const& _sorted_token, NrnThread* _nt, Memb_list* _ml_arg, int _type) {
+        _nrn_mechanism_cache_range _lmr{_sorted_token, *_nt, *_ml_arg, _type};
+        auto inst = make_instance_test_pp(_lmr);
+        auto node_data = make_node_data_test_pp(*_nt, *_ml_arg);
+        auto nodecount = _ml_arg->nodecount;
+        for (int id = 0; id < nodecount; id++) {
+        }
+    }
 
 
     static void _initlists() {