diff --git a/CHANGELOG.md b/CHANGELOG.md
index f7742cb5..87679299 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,8 +10,15 @@ list yields a list of all related PRs for each release.
 
 # [unreleased]
 
+## Added
+
 - Startracker temperature set and PCDU switcher set are diagnostic now
 
+## Fixed
+
+- MGM4 handling in ACS sensor processing: Bugfix in `mulScalar` operation
+  PR: https://egit.irs.uni-stuttgart.de/eive/eive-obsw/pulls/354
+
 # [v1.20.0] 2023-01-24
 
 ## Added
diff --git a/mission/controller/acs/SensorProcessing.cpp b/mission/controller/acs/SensorProcessing.cpp
index 4635e673..ac2e5752 100644
--- a/mission/controller/acs/SensorProcessing.cpp
+++ b/mission/controller/acs/SensorProcessing.cpp
@@ -103,7 +103,7 @@ void SensorProcessing::processMgm(const float *mgm0Value, bool mgm0valid, const
   }
   if (mgm4valid) {
     float mgm4ValueNT[3];
-    VectorOperations<float>::mulScalar(mgm4Value, 1e3, mgm4ValueNT, 3);  // uT to nT
+    VectorOperations<float>::mulScalar(mgm4Value, 1e-3, mgm4ValueNT, 3);  // uT to nT
     VectorOperations<float>::subtract(mgm4ValueNT, mgmParameters->mgm4hardIronOffset,
                                       mgm4ValueNoBias, 3);
     MatrixOperations<float>::multiply(mgmParameters->mgm4softIronInverse[0], mgm4ValueNoBias,