diff --git a/src/mckicad/tools/schematic_analysis.py b/src/mckicad/tools/schematic_analysis.py
index 7f6f799..0e621c9 100644
--- a/src/mckicad/tools/schematic_analysis.py
+++ b/src/mckicad/tools/schematic_analysis.py
@@ -178,6 +178,7 @@ def _build_connectivity(
     # --- 2. Map component pin positions to coordinates ---
     pin_at: dict[tuple[float, float], list[dict[str, str]]] = {}
     all_pins: list[tuple[str, str, tuple[float, float]]] = []
+    refs_with_pins: set[str] = set()
 
     for comp in getattr(sch, "components", []):
         ref = getattr(comp, "reference", None)
@@ -190,9 +191,42 @@ def _build_connectivity(
                 entry = {"reference": str(ref), "pin": str(pin_num)}
                 pin_at.setdefault(coord, []).append(entry)
                 all_pins.append((str(ref), str(pin_num), coord))
+                refs_with_pins.add(str(ref))
         except Exception:
             pass
 
+    # 2b. Fallback: for components where list_component_pins() returned
+    # nothing (custom library symbols), extract pins from the raw
+    # (lib_symbols ...) section via the S-expression parser.
+    if schematic_path:
+        for comp in getattr(sch, "components", []):
+            ref = getattr(comp, "reference", None)
+            if not ref or str(ref) in refs_with_pins:
+                continue
+            lib_id = getattr(comp, "lib_id", None)
+            if not lib_id:
+                continue
+            sexp_pins = parse_lib_symbol_pins(schematic_path, str(lib_id))
+            if not sexp_pins:
+                continue
+
+            comp_pos = getattr(comp, "position", None)
+            comp_rot = float(getattr(comp, "rotation", 0) or 0)
+            comp_mirror = getattr(comp, "mirror", None)
+            mirror_x = comp_mirror in ("x", True) if comp_mirror else False
+            cx = float(comp_pos.x) if comp_pos is not None and hasattr(comp_pos, "x") else 0.0
+            cy = float(comp_pos.y) if comp_pos is not None and hasattr(comp_pos, "y") else 0.0
+
+            for sp in sexp_pins:
+                sx, sy = transform_pin_to_schematic(
+                    sp["x"], sp["y"], cx, cy, comp_rot, mirror_x
+                )
+                coord = _rc(sx, sy)
+                _find(coord)
+                entry = {"reference": str(ref), "pin": sp["number"]}
+                pin_at.setdefault(coord, []).append(entry)
+                all_pins.append((str(ref), sp["number"], coord))
+
     # --- 3. Map labels to coordinates (labels name nets) ---
     label_at: dict[tuple[float, float], str] = {}