diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1fdc3e1f..a3b7a3d4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -20,6 +20,11 @@ will consitute of a breaking change warranting a new major release:
 
 - Move ACS board polling to separate worker thread.
 
+## Fixed
+
+- Linux GPS handler now checks the individual `*_SET` flags when analysing the `gpsd` struct.
+  PR: https://egit.irs.uni-stuttgart.de/eive/eive-obsw/pulls/400
+
 # [v1.32.0]
 
 eive-tmtc: v2.16.1
diff --git a/linux/devices/GpsHyperionLinuxController.cpp b/linux/devices/GpsHyperionLinuxController.cpp
index a6e0a1a3..3b396504 100644
--- a/linux/devices/GpsHyperionLinuxController.cpp
+++ b/linux/devices/GpsHyperionLinuxController.cpp
@@ -172,20 +172,10 @@ bool GpsHyperionLinuxController::readGpsDataFromGpsd() {
         return false;
       }
       oneShotSwitches.gpsReadFailedSwitch = true;
-      // did not event get mode, nothing to see.
-      if (MODE_SET != (MODE_SET & gps.set)) {
-        if (mode != MODE_OFF) {
-          if (maxTimeToReachFix.hasTimedOut() and oneShotSwitches.cantGetFixSwitch) {
-            sif::warning
-                << "GPSHyperionHandler::readGpsDataFromGpsd: No mode could be set in allowed "
-                << maxTimeToReachFix.timeout / 1000 << " seconds" << std::endl;
-            triggerEvent(GpsHyperion::CANT_GET_FIX, maxTimeToReachFix.timeout);
-            oneShotSwitches.cantGetFixSwitch = false;
-          }
-          // Mode is on, so do next read immediately
-          return true;
-        }
-        // GPS device is off anyway, so do other handling
+      ReturnValue_t result = handleGpsReadData();
+      if (result == returnvalue::OK) {
+        return true;
+      } else {
         return false;
       }
       noModeSetCntr = 0;
@@ -197,11 +187,26 @@ bool GpsHyperionLinuxController::readGpsDataFromGpsd() {
                   "SHM read not implemented"
                << std::endl;
   }
-  handleGpsReadData();
   return true;
 }
 
 ReturnValue_t GpsHyperionLinuxController::handleGpsReadData() {
+  bool modeIsSet = true;
+  if (MODE_SET != (MODE_SET & gps.set)) {
+    if (mode != MODE_OFF) {
+      if (maxTimeToReachFix.hasTimedOut() and oneShotSwitches.cantGetFixSwitch) {
+        sif::warning << "GpsHyperionLinuxController: No mode could be set in allowed "
+                     << maxTimeToReachFix.timeout / 1000 << " seconds" << std::endl;
+        triggerEvent(GpsHyperion::CANT_GET_FIX, maxTimeToReachFix.timeout);
+        oneShotSwitches.cantGetFixSwitch = false;
+      }
+      modeIsSet = false;
+    } else {
+      // GPS device is off anyway, so do other handling
+      return returnvalue::FAILED;
+    }
+  }
+
   PoolReadGuard pg(&gpsSet);
   if (pg.getReadResult() != returnvalue::OK) {
 #if FSFW_VERBOSE_LEVEL >= 1
@@ -211,66 +216,93 @@ ReturnValue_t GpsHyperionLinuxController::handleGpsReadData() {
   }
 
   bool validFix = false;
-  // 0: Not seen, 1: No fix, 2: 2D-Fix, 3: 3D-Fix
-  if (gps.fix.mode == 2 or gps.fix.mode == 3) {
-    validFix = true;
-  }
-  if (gpsSet.fixMode.value != gps.fix.mode) {
-    triggerEvent(GpsHyperion::GPS_FIX_CHANGE, gpsSet.fixMode.value, gps.fix.mode);
-  }
-  gpsSet.fixMode.value = gps.fix.mode;
-  if (gps.fix.mode == 0 or gps.fix.mode == 1) {
-    if (modeCommanded and maxTimeToReachFix.hasTimedOut()) {
-      // We are supposed to be on and functioning, but no fix was found
-      if (mode == MODE_ON or mode == MODE_NORMAL) {
-        mode = MODE_OFF;
-      }
-      modeCommanded = false;
+  if (modeIsSet) {
+    // 0: Not seen, 1: No fix, 2: 2D-Fix, 3: 3D-Fix
+    if (gps.fix.mode == 2 or gps.fix.mode == 3) {
+      validFix = true;
+    }
+    if (gpsSet.fixMode.value != gps.fix.mode) {
+      triggerEvent(GpsHyperion::GPS_FIX_CHANGE, gpsSet.fixMode.value, gps.fix.mode);
+    }
+    gpsSet.fixMode.value = gps.fix.mode;
+    if (gps.fix.mode == 0 or gps.fix.mode == 1) {
+      if (modeCommanded and maxTimeToReachFix.hasTimedOut()) {
+        // We are supposed to be on and functioning, but no fix was found
+        if (mode == MODE_ON or mode == MODE_NORMAL) {
+          mode = MODE_OFF;
+        }
+        modeCommanded = false;
+      }
+    }
+  }
+  gpsSet.fixMode.setValid(modeIsSet);
+
+  // Only set on specific messages, so only set a valid flag to invalid
+  // if not set for more than a full message set (10 messages here)
+  if (SATELLITE_SET == (SATELLITE_SET & gps.set)) {
+    gpsSet.satInUse.value = gps.satellites_used;
+    gpsSet.satInView.value = gps.satellites_visible;
+    if (not gpsSet.satInUse.isValid()) {
+      gpsSet.satInUse.setValid(true);
+      gpsSet.satInView.setValid(true);
+    }
+    satNotSetCounter = 0;
+  } else {
+    satNotSetCounter++;
+    if (gpsSet.satInUse.isValid() and satNotSetCounter >= 10) {
+      gpsSet.satInUse.setValid(false);
+      gpsSet.satInView.setValid(false);
     }
-    gpsSet.setValidity(false, true);
-  } else if (gps.satellites_used > 0 && validFix && mode != MODE_OFF) {
-    gpsSet.setValidity(true, true);
   }
 
-  gpsSet.satInUse.value = gps.satellites_used;
-  gpsSet.satInView.value = gps.satellites_visible;
-
+  // LATLON is set for every message, no need for a counter
   bool latValid = false;
-  if (std::isfinite(gps.fix.latitude)) {
-    // Negative latitude -> South direction
-    gpsSet.latitude.value = gps.fix.latitude;
-    if (gps.fix.mode >= 2) {
-      latValid = true;
+  bool longValid = false;
+  if (LATLON_SET == (LATLON_SET & gps.set)) {
+    if (std::isfinite(gps.fix.latitude)) {
+      // Negative latitude -> South direction
+      gpsSet.latitude.value = gps.fix.latitude;
+      // As specified in gps.h: Only valid if mode >= 2
+      if (gps.fix.mode >= 2) {
+        latValid = true;
+      }
+    }
+
+    if (std::isfinite(gps.fix.longitude)) {
+      // Negative longitude -> West direction
+      gpsSet.longitude.value = gps.fix.longitude;
+      // As specified in gps.h: Only valid if mode >= 2
+      if (gps.fix.mode >= 2) {
+        longValid = true;
+      }
     }
   }
   gpsSet.latitude.setValid(latValid);
+  gpsSet.longitude.setValid(longValid);
 
-  bool longValid = false;
-  if (std::isfinite(gps.fix.longitude)) {
-    // Negative longitude -> West direction
-    gpsSet.longitude.value = gps.fix.longitude;
-    if (gps.fix.mode >= 2) {
-      longValid = true;
-    }
-  }
-  gpsSet.latitude.setValid(longValid);
-
+  // ALTITUDE is set for every message, no need for a counter
   bool altitudeValid = false;
-  if (std::isfinite(gps.fix.altitude)) {
+  if (ALTITUDE_SET == (ALTITUDE_SET & gps.set) && std::isfinite(gps.fix.altitude)) {
     gpsSet.altitude.value = gps.fix.altitude;
+    // As specified in gps.h: Only valid if mode == 3
     if (gps.fix.mode == 3) {
       altitudeValid = true;
     }
   }
   gpsSet.altitude.setValid(altitudeValid);
 
-  if (std::isfinite(gps.fix.speed)) {
+  // SPEED is set for every message, no need for a counter
+  bool speedValid = false;
+  if (SPEED_SET == (SPEED_SET & gps.set) && std::isfinite(gps.fix.speed)) {
     gpsSet.speed.value = gps.fix.speed;
-  } else {
-    gpsSet.speed.setValid(false);
+    speedValid = true;
   }
+  gpsSet.speed.setValid(speedValid);
 
+  // TIME is set for every message, no need for a counter
+  bool timeValid = false;
   if (TIME_SET == (TIME_SET & gps.set)) {
+    timeValid = true;
     timeval time = {};
 #if LIBGPS_VERSION_MINOR <= 17
     gpsSet.unixSeconds.value = std::floor(gps.fix.time);
@@ -294,15 +326,14 @@ ReturnValue_t GpsHyperionLinuxController::handleGpsReadData() {
     gpsSet.hours = timeOfDay.hour;
     gpsSet.minutes = timeOfDay.minute;
     gpsSet.seconds = timeOfDay.second;
-  } else {
-    gpsSet.unixSeconds.setValid(false);
-    gpsSet.year.setValid(false);
-    gpsSet.month.setValid(false);
-    gpsSet.day.setValid(false);
-    gpsSet.hours.setValid(false);
-    gpsSet.minutes.setValid(false);
-    gpsSet.seconds.setValid(false);
   }
+  gpsSet.unixSeconds.setValid(timeValid);
+  gpsSet.year.setValid(timeValid);
+  gpsSet.month.setValid(timeValid);
+  gpsSet.day.setValid(timeValid);
+  gpsSet.hours.setValid(timeValid);
+  gpsSet.minutes.setValid(timeValid);
+  gpsSet.seconds.setValid(timeValid);
 
   if (debugHyperionGps) {
     sif::info << "-- Hyperion GPS Data --" << std::endl;
diff --git a/linux/devices/GpsHyperionLinuxController.h b/linux/devices/GpsHyperionLinuxController.h
index 1e97bc29..df08d8a4 100644
--- a/linux/devices/GpsHyperionLinuxController.h
+++ b/linux/devices/GpsHyperionLinuxController.h
@@ -61,6 +61,8 @@ class GpsHyperionLinuxController : public ExtendedControllerBase {
   Countdown maxTimeToReachFix = Countdown(MAX_SECONDS_TO_REACH_FIX * 1000);
   bool modeCommanded = false;
   bool timeInit = false;
+  uint8_t satNotSetCounter = 0;
+
 #if OBSW_THREAD_TRACING == 1
   uint32_t opCounter = 0;
 #endif