diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_JRE_Serial.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_JRE_Serial.cpp
index 5766ac219d8d5e..df742fda80ede1 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_JRE_Serial.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_JRE_Serial.cpp
@@ -13,11 +13,13 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include "AP_RangeFinder_JRE_Serial.h"
-#include <AP_Math/AP_Math.h>
+#include "AP_RangeFinder_config.h"
 
 #if AP_RANGEFINDER_JRE_SERIAL_ENABLED
 
+#include "AP_RangeFinder_JRE_Serial.h"
+#include <AP_Math/AP_Math.h>
+
 #define FRAME_HEADER_1   'R'    // 0x52
 #define FRAME_HEADER_2   'A'    // 0x41
 
@@ -30,15 +32,10 @@ bool AP_RangeFinder_JRE_Serial::get_reading(float &reading_m)
     if (uart == nullptr) {
         return false;  // not update
     }
-    uint32_t n = uart->available();
-    if (n == 0) {
-        return false;
-    }
 
     uint16_t valid_count = 0;   // number of valid readings
     uint16_t invalid_count = 0; // number of invalid readings
     float sum = 0;
-    float reading_cm;
     // max distance the sensor can reliably measure - read from parameters
     const int16_t distance_cm_max = max_distance_cm();
 
@@ -71,17 +68,12 @@ bool AP_RangeFinder_JRE_Serial::get_reading(float &reading_m)
             if (data_buff_idx >= ARRAY_SIZE(data_buff)) {  // 1 data set complete
                 // crc check
                 uint16_t crc = crc16_ccitt_r(data_buff, ARRAY_SIZE(data_buff) - 2, 0xffff, 0xffff);
-                if ((((crc>>8) & 0xff) == data_buff[15]) && ((crc & 0xff) == data_buff[14])) {
+                if ((HIGHBYTE(crc) == data_buff[15]) && (LOWBYTE(crc) == data_buff[14])) {
                     // status check
                     if (data_buff[13] & 0x02) { // NTRK
                         invalid_count++;
                     } else { // TRK
-                        reading_cm = data_buff[4] * 256 + data_buff[5];
-                        if (reading_cm < distance_cm_max) {
-                            reading_m = reading_cm * 0.01f;
-                        } else {
-                            reading_m = distance_cm_max * 0.01f;
-                        }
+                        reading_m = (data_buff[4] * 256 + data_buff[5]) * 0.01f;
                         sum += reading_m;
                         valid_count++;
                     }
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_JRE_Serial.h b/libraries/AP_RangeFinder/AP_RangeFinder_JRE_Serial.h
index 03115917a5c005..91b2c6a1f13ada 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_JRE_Serial.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_JRE_Serial.h
@@ -1,10 +1,12 @@
 #pragma once
 
-#include "AP_RangeFinder.h"
-#include "AP_RangeFinder_Backend_Serial.h"
+#include "AP_RangeFinder_config.h"
 
 #if AP_RANGEFINDER_JRE_SERIAL_ENABLED
 
+#include "AP_RangeFinder.h"
+#include "AP_RangeFinder_Backend_Serial.h"
+
 #define DATA_LENGTH 16
 
 class AP_RangeFinder_JRE_Serial : public AP_RangeFinder_Backend_Serial