diff --git a/npf.c b/npf.c
index ea48a82340..5e42c10db4 100644
--- a/npf.c
+++ b/npf.c
@@ -300,7 +300,7 @@ int32 NPFRailPathCost(AyStar* as, AyStarNode* current, OpenListNode* parent) {
 				 * encounter, if it is red */
 
 				/* Is this a presignal exit or combo? */
-				SignalType sigtype = GetSignalType(tile, trackdir);
+				SignalType sigtype = GetSignalType(tile, TrackdirToTrack(trackdir));
 				if (sigtype == SIGTYPE_EXIT || sigtype == SIGTYPE_COMBO)
 					/* Penalise exit and combo signals differently (heavier) */
 					cost += _patches.npf_rail_firstred_exit_penalty;