diff --git a/extract/aux_platform.go b/extract/aux_platform.go
index 1ea4462..1f9d739 100644
--- a/extract/aux_platform.go
+++ b/extract/aux_platform.go
@@ -322,9 +322,9 @@ func (ap *AuxPlatform) Parse(data []byte) error {
 	ap.MemsGyroXAV = float64(bigEndianToInt32(data[479:483])) * 0.000001
 	ap.MemsGyroYAV = float64(bigEndianToInt32(data[483:487])) * 0.000001
 	ap.MemsGyroZAV = float64(bigEndianToInt32(data[487:491])) * 0.000001
-	ap.MagnetictrengthX = float64(bigEndianToInt16(data[491:495])) * 19200
-	ap.MagnetictrengthY = float64(bigEndianToInt16(data[495:499])) * 19200
-	ap.MagnetictrengthZ = float64(bigEndianToInt16(data[499:503])) * 19200
+	ap.MagnetictrengthX = float64(bigEndianToInt32(data[491:495])) * 19200
+	ap.MagnetictrengthY = float64(bigEndianToInt32(data[495:499])) * 19200
+	ap.MagnetictrengthZ = float64(bigEndianToInt32(data[499:503])) * 19200
 	ap.ASSTimeInt = binary.BigEndian.Uint32(data[503:507])
 	ap.ASSTimeDec = uint32(data[507])<<16 | uint32(data[508])<<8 | uint32(data[509])
 	ap.CheckSum = data[511]