diff --git a/docs/research/pre_work_error_ledger.md b/docs/research/pre_work_error_ledger.md
index 8d1567ec..d03a4b1a 100644
--- a/docs/research/pre_work_error_ledger.md
+++ b/docs/research/pre_work_error_ledger.md
@@ -85,6 +85,7 @@ For large architecture or release work, also read:
 | ERR-052 | Text-only privacy scanning cannot distinguish a harmless quoted placeholder from a bare Python identifier that will fail at runtime. | mitigated 2026-07-13 | `public_release_privacy_scan.py` parses shipped Python files and rejects executable `REDACTED_*` names; keep the AST regression test. |
 | ERR-053 | A parity manifest could label an external engine `official_verified` without a raw artifact, hash, or calculation settings, making claimed oracle closure unverifiable. | mitigated 2026-07-13 | `three_engine_parity_replay_validator.py` requires raw artifact existence, SHA-256 and settings for verified/imported external engines; otherwise parity is `invalid`. |
 | ERR-054 | Candidate-time sensitivity scanning used the legacy `varga` CLI, so D4/D24/D30 could appear unavailable despite being supported by `varga-full`. | resolved 2026-07-13 | Scanner calls `varga-full --divisions D4,D9,D10,D24,D30` once per candidate and reads its canonical `Ascendant.sign` fields. |
+| ERR-055 | The full-reading path called `calc_all_sahams()` without lat/lon/tz, so an otherwise computable Swiss day/night context was silently blocked. | resolved 2026-07-14 | Pass the calculation arguments' lat/lon/tz into the Saham layer; keep Saham formula maturity `partial` until oracle parity exists. |
 
 ## Fragment Sweep Command Set
 
diff --git a/scripts/jyotish_engine.py b/scripts/jyotish_engine.py
index 047853d0..930dda90 100644
--- a/scripts/jyotish_engine.py
+++ b/scripts/jyotish_engine.py
@@ -5100,7 +5100,14 @@ def cmd_full_reading(args):
         # Sahams（特殊点）—— 需要出生时间
         birth_dt = getattr(args, 'birth_datetime', None)
         if birth_dt and planet_lons:
-            sahams_result = calc_all_sahams(planet_lons, asc_deg, birth_dt)
+            sahams_result = calc_all_sahams(
+                planet_lons,
+                asc_deg,
+                birth_dt,
+                lat=getattr(args, 'lat', None),
+                lon=getattr(args, 'lon', None),
+                tz=getattr(args, 'tz', None),
+            )
             report['modules']['sahams'] = sahams_result
         else:
             report['modules']['sahams'] = {'warning': 'birth_datetime or planet_lons missing, skip saham calc'}