diff --git a/src/spicelib/devices/vdmos/vdmosacld.c b/src/spicelib/devices/vdmos/vdmosacld.c
index 6a5276372..2a95a90e2 100644
--- a/src/spicelib/devices/vdmos/vdmosacld.c
+++ b/src/spicelib/devices/vdmos/vdmosacld.c
@@ -35,7 +35,7 @@ VDMOSacLoad(GENmodel *inModel, CKTcircuit *ckt)
         for(here = VDMOSinstances(model); here!= NULL;
                 here = VDMOSnextInstance(here)) {
 
-            selfheat = (here->VDMOStnodeoutGiven) && (model->VDMOSrthjc != 0.0);
+            selfheat = (here->VDMOStnodeoutGiven) && (model->VDMOSrthjcGiven);
             if (here->VDMOSmode < 0) {
                 xnrm=0;
                 xrev=1;
diff --git a/src/spicelib/devices/vdmos/vdmosdefs.h b/src/spicelib/devices/vdmos/vdmosdefs.h
index 6aaee1645..8fe805a0d 100644
--- a/src/spicelib/devices/vdmos/vdmosdefs.h
+++ b/src/spicelib/devices/vdmos/vdmosdefs.h
@@ -42,8 +42,8 @@ typedef struct sVDMOSinstance {
     const int VDMOSdNode;  /* number of the gate node of the mosfet */
     const int VDMOSgNode;  /* number of the gate node of the mosfet */
     const int VDMOSsNode;  /* number of the source node of the mosfet */
-    const int VDMOStempNode;  /* number of the temperature node of the mosfet */
-    const int VDMOStcaseNode;  /* number of the 2nd temperature node of the mosfet */
+    int VDMOStempNode;  /* number of the temperature node of the mosfet */
+    int VDMOStcaseNode;  /* number of the 2nd temperature node of the mosfet */
     int VDMOSdNodePrime; /* number of the internal drain node of the mosfet */
     int VDMOSsNodePrime; /* number of the internal source node of the mosfet */
     int VDMOSgNodePrime; /* number of the internal gate node of the mosfet */
diff --git a/src/spicelib/devices/vdmos/vdmosload.c b/src/spicelib/devices/vdmos/vdmosload.c
index 55ff97a41..233eb6100 100644
--- a/src/spicelib/devices/vdmos/vdmosload.c
+++ b/src/spicelib/devices/vdmos/vdmosload.c
@@ -104,7 +104,7 @@ VDMOSload(GENmodel *inModel, CKTcircuit *ckt)
         for (here = VDMOSinstances(model); here != NULL;
                 here = VDMOSnextInstance(here)) {
 
-            selfheat = (here->VDMOStnodeoutGiven) && (model->VDMOSrthjc != 0.0);
+            selfheat = (here->VDMOStnodeoutGiven) && (model->VDMOSrthjcGiven);
             if (selfheat)
                 Check_mos = 1;
             else
diff --git a/src/spicelib/devices/vdmos/vdmosnoi.c b/src/spicelib/devices/vdmos/vdmosnoi.c
index 222f686be..48fe0dda8 100644
--- a/src/spicelib/devices/vdmos/vdmosnoi.c
+++ b/src/spicelib/devices/vdmos/vdmosnoi.c
@@ -91,7 +91,7 @@ VDMOSnoise (int mode, int operation, GENmodel *genmodel, CKTcircuit *ckt,
         switch (mode) {
 
         case N_DENS:
-            if ((inst->VDMOStnodeoutGiven) && (model->VDMOSrthjc != 0.0))  
+            if ((inst->VDMOStnodeoutGiven) && (model->VDMOSrthjcGiven))  
                 tempRatioSH = inst->VDMOSTempSH / ckt->CKTtemp;
             else
                 tempRatioSH = 1.0;
diff --git a/src/spicelib/devices/vdmos/vdmosset.c b/src/spicelib/devices/vdmos/vdmosset.c
index e8aa30fdf..c763b76bc 100644
--- a/src/spicelib/devices/vdmos/vdmosset.c
+++ b/src/spicelib/devices/vdmos/vdmosset.c
@@ -119,7 +119,7 @@ VDMOSsetup(SMPmatrix *matrix, GENmodel *inModel, CKTcircuit *ckt,
             model->VDMOSeg = 1.11;
 
         if (!model->VDMOSrthjcGiven)
-            model->VDMOSrthjc = 0;
+            model->VDMOSrthjc = 1.0e-03;
 
         if (!model->VDMOSrthcaGiven)
             model->VDMOSrthca = 100;
@@ -312,17 +312,30 @@ VDMOSsetup(SMPmatrix *matrix, GENmodel *inModel, CKTcircuit *ckt,
                 here->VDIOposPrimeNode = here->VDMOSsNode;
             }
 
-            if ((here->VDMOStnodeoutGiven) && (model->VDMOSrthjc!=0.0)) {
-                if(here->VDMOSvcktTbranch == 0) {
+            if ((here->VDMOStnodeoutGiven) && (model->VDMOSrthjcGiven)) {
+               if (here->VDMOStempNode == -1) {
+                  error = CKTmkVolt(ckt,&tmp,here->VDMOSname,"Tj");
+                  if (error) return(error);
+                     here->VDMOStempNode = tmp->number;
+               }
+               if (here->VDMOStcaseNode == -1) {
+                  error = CKTmkVolt(ckt,&tmp,here->VDMOSname,"Tc");
+                  if (error) return(error);
+                     here->VDMOStcaseNode = tmp->number;
+               }
+               if(here->VDMOSvcktTbranch == 0) {
                     error = CKTmkCur(ckt,&tmp,here->VDMOSname,"VcktTemp");
                     if(error) return(error);
                     here->VDMOSvcktTbranch = tmp->number;
-                } 
+                }
                 if (here->VDMOStNodePrime == 0) {
-                    error = CKTmkVolt(ckt, &tmp, here->VDMOSname, "thermal node");
+                    error = CKTmkVolt(ckt, &tmp, here->VDMOSname, "cktTemp");
                     if (error) return(error);
                     here->VDMOStNodePrime = tmp->number;
                 }
+            } else {
+                here->VDMOStempNode = 0;
+                here->VDMOStcaseNode = 0;
             }
 
             /* macro to make elements with built in test for out of memory */
@@ -331,7 +344,7 @@ do { if((here->ptr = SMPmakeElt(matrix, here->first, here->second)) == NULL){\
     return(E_NOMEM);\
 } } while(0)
 
-            if ((here->VDMOStnodeoutGiven) && (model->VDMOSrthjc!=0.0)) {
+            if ((here->VDMOStnodeoutGiven) && (model->VDMOSrthjcGiven)) {
                 TSTALLOC(VDMOSTemptempPtr, VDMOStempNode, VDMOStempNode);
                 TSTALLOC(VDMOSTempdpPtr, VDMOStempNode, VDMOSdNodePrime);
                 TSTALLOC(VDMOSTempspPtr, VDMOStempNode, VDMOSsNodePrime);
@@ -415,7 +428,7 @@ VDMOSunsetup(GENmodel *inModel, CKTcircuit *ckt)
                 CKTdltNNum(ckt, here->VDIOposPrimeNode);
             here->VDIOposPrimeNode = 0;
 
-            if ((here->VDMOStnodeoutGiven) && (model->VDMOSrthjc!=0.0)) {
+            if ((here->VDMOStnodeoutGiven) && (model->VDMOSrthjcGiven)) {
                 if (here->VDMOStNodePrime > 0)
                     CKTdltNNum(ckt, here->VDMOStNodePrime);
                 here->VDMOStNodePrime = 0;