diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.cpp
index 58b13635d2..34614ea899 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.cpp
@@ -17,7 +17,6 @@
 #include <GCS_MAVLink/GCS.h>
 #include "AP_RangeFinder_BLPing.h"
 
-#define BLPING_TIMEOUT_MS       500     // sensor timeout after 0.5 sec
 #define BLPING_INIT_RATE_MS     1000    // initialise sensor at no more than 1hz
 #define BLPING_FRAME_HEADER1    0x42    // header first byte ('B')
 #define BLPING_FRAME_HEADER2    0x52    // header second byte ('R')
@@ -53,16 +52,10 @@ void AP_RangeFinder_BLPing::update(void)
     if (uart == nullptr) {
         return;
     }
+    AP_RangeFinder_Backend_Serial::update();
 
-    const uint32_t now = AP_HAL::millis();
-
-    if (get_reading(state.distance_cm)) {
-        // update range_valid state based on distance measured
-        state.last_reading_ms = now;
-        update_status();
-    } else if (now - state.last_reading_ms > BLPING_TIMEOUT_MS) {
-        set_status(RangeFinder::Status::NoData);
-
+    if (status() == RangeFinder::Status::NoData) {
+        const uint32_t now = AP_HAL::millis();
         // initialise sensor if no distances recently
         if (now - last_init_ms > BLPING_INIT_RATE_MS) {
             last_init_ms = now;
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.h b/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.h
index 46ac8b8100..998dced221 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.h
@@ -29,6 +29,8 @@ private:
     // read a distance from the sensor
     bool get_reading(uint16_t &reading_cm) override;
 
+    uint16_t read_timeout_ms() const override { return 500; }
+
     // process one byte received on serial port
     // returns true if a distance message has been successfully parsed
     // state is stored in msg structure
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Benewake.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_Benewake.cpp
index 6877aaba28..aa2bf2d05a 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Benewake.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Benewake.cpp
@@ -132,17 +132,3 @@ bool AP_RangeFinder_Benewake::get_reading(uint16_t &reading_cm)
     // no readings so return false
     return false;
 }
-
-/* 
-   update the state of the sensor
-*/
-void AP_RangeFinder_Benewake::update(void)
-{
-    if (get_reading(state.distance_cm)) {
-        // update range_valid state based on distance measured
-        state.last_reading_ms = AP_HAL::millis();
-        update_status();
-    } else if (AP_HAL::millis() - state.last_reading_ms > 200) {
-        set_status(RangeFinder::Status::NoData);
-    }
-}
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Benewake.h b/libraries/AP_RangeFinder/AP_RangeFinder_Benewake.h
index 2d9b90df8e..53e0cf5851 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Benewake.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Benewake.h
@@ -10,9 +10,6 @@ public:
 
     using AP_RangeFinder_Backend_Serial::AP_RangeFinder_Backend_Serial;
 
-    // update state
-    void update(void) override;
-
 protected:
 
     virtual MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Lanbao.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_Lanbao.cpp
index 60f51346e7..1da6a423fe 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Lanbao.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Lanbao.cpp
@@ -80,17 +80,3 @@ bool AP_RangeFinder_Lanbao::get_reading(uint16_t &reading_cm)
     }
     return false;
 }
-
-/* 
-   update the state of the sensor
-*/
-void AP_RangeFinder_Lanbao::update(void)
-{
-    if (get_reading(state.distance_cm)) {
-        // update range_valid state based on distance measured
-        state.last_reading_ms = AP_HAL::millis();
-        update_status();
-    } else if (AP_HAL::millis() - state.last_reading_ms > 200) {
-        set_status(RangeFinder::Status::NoData);
-    }
-}
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Lanbao.h b/libraries/AP_RangeFinder/AP_RangeFinder_Lanbao.h
index 7e88d13a82..fc44bde204 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Lanbao.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Lanbao.h
@@ -15,9 +15,6 @@ public:
         return 115200;
     }
 
-    // update state
-    void update(void) override;
-
 protected:
 
     virtual MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_LeddarOne.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_LeddarOne.cpp
index 0cf3fafb56..da79fe01db 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_LeddarOne.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_LeddarOne.cpp
@@ -96,20 +96,6 @@ bool AP_RangeFinder_LeddarOne::get_reading(uint16_t &reading_cm)
     return false;
 }
 
-/*
-   update the state of the sensor
-*/
-void AP_RangeFinder_LeddarOne::update(void)
-{
-    if (get_reading(state.distance_cm)) {
-        // update range_valid state based on distance measured
-        state.last_reading_ms = AP_HAL::millis();
-        update_status();
-    } else if (AP_HAL::millis() - state.last_reading_ms > 200) {
-        set_status(RangeFinder::Status::NoData);
-    }
-}
-
 /*
    CRC16
    CRC-16-IBM(x16+x15+x2+1)
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_LeddarOne.h b/libraries/AP_RangeFinder/AP_RangeFinder_LeddarOne.h
index d67cf4028c..64ab648fbc 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_LeddarOne.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_LeddarOne.h
@@ -44,9 +44,6 @@ public:
 
     using AP_RangeFinder_Backend_Serial::AP_RangeFinder_Backend_Serial;
 
-    // update state
-    void update(void) override;
-
 protected:
 
     virtual MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_LightWareSerial.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_LightWareSerial.cpp
index ed6e1a3597..97355b1af0 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_LightWareSerial.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_LightWareSerial.cpp
@@ -85,17 +85,3 @@ bool AP_RangeFinder_LightWareSerial::get_reading(uint16_t &reading_cm)
     // no readings so return false
     return false;
 }
-
-/* 
-   update the state of the sensor
-*/
-void AP_RangeFinder_LightWareSerial::update(void)
-{
-    if (get_reading(state.distance_cm)) {
-        // update range_valid state based on distance measured
-        state.last_reading_ms = AP_HAL::millis();
-        update_status();
-    } else if (AP_HAL::millis() - state.last_reading_ms > 200) {
-        set_status(RangeFinder::Status::NoData);
-    }
-}
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_LightWareSerial.h b/libraries/AP_RangeFinder/AP_RangeFinder_LightWareSerial.h
index cb00f68204..70c4a6ced6 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_LightWareSerial.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_LightWareSerial.h
@@ -10,9 +10,6 @@ public:
 
     using AP_RangeFinder_Backend_Serial::AP_RangeFinder_Backend_Serial;
 
-    // update state
-    void update(void) override;
-
 protected:
 
     virtual MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.cpp
index d89d611a6e..2b1acc25c3 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.cpp
@@ -60,17 +60,3 @@ bool AP_RangeFinder_MaxsonarSerialLV::get_reading(uint16_t &reading_cm)
 
     return true;
 }
-
-/* 
-   update the state of the sensor
-*/
-void AP_RangeFinder_MaxsonarSerialLV::update(void)
-{
-    if (get_reading(state.distance_cm)) {
-        // update range_valid state based on distance measured
-        state.last_reading_ms = AP_HAL::millis();
-        update_status();
-    } else if (AP_HAL::millis() - state.last_reading_ms > 500) {
-        set_status(RangeFinder::Status::NoData);
-    }
-}
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.h b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.h
index bface028d4..200a5dd341 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.h
@@ -10,9 +10,6 @@ public:
 
     using AP_RangeFinder_Backend_Serial::AP_RangeFinder_Backend_Serial;
 
-    // update state
-    void update(void) override;
-
 protected:
 
     MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
@@ -23,6 +20,8 @@ private:
     // get a reading
     bool get_reading(uint16_t &reading_cm) override;
 
+    uint16_t read_timeout_ms() const override { return 500; }
+
     char linebuf[10];
     uint8_t linebuf_len = 0;
 };
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.cpp
index a13d3cfd8f..37788b968a 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.cpp
@@ -20,19 +20,6 @@
 
 extern const AP_HAL::HAL& hal;
 
-// update the state of the sensor
-void AP_RangeFinder_NMEA::update(void)
-{
-    uint32_t now = AP_HAL::millis();
-    if (get_reading(state.distance_cm)) {
-        // update range_valid state based on distance measured
-        state.last_reading_ms = now;
-        update_status();
-    } else if ((now - state.last_reading_ms) > 3000) {
-        set_status(RangeFinder::Status::NoData);
-    }
-}
-
 // return last value measured by sensor
 bool AP_RangeFinder_NMEA::get_reading(uint16_t &reading_cm)
 {
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.h b/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.h
index af64a6ac86..e55879fec7 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.h
@@ -25,9 +25,6 @@ public:
 
     using AP_RangeFinder_Backend_Serial::AP_RangeFinder_Backend_Serial;
 
-    // update state
-    void update(void) override;
-
 protected:
 
     virtual MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
@@ -46,6 +43,8 @@ private:
     // get a reading
     bool get_reading(uint16_t &reading_cm) override;
 
+    uint16_t read_timeout_ms() const override { return 3000; }
+
     // add a single character to the buffer and attempt to decode
     // returns true if a complete sentence was successfully decoded
     // distance should be pulled directly from _distance_m member
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_uLanding.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_uLanding.cpp
index dc2d13781b..333ccaedf8 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_uLanding.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_uLanding.cpp
@@ -173,17 +173,3 @@ bool AP_RangeFinder_uLanding::get_reading(uint16_t &reading_cm)
 
     return true;
 }
-
-/*
-   update the state of the sensor
-*/
-void AP_RangeFinder_uLanding::update(void)
-{
-    if (get_reading(state.distance_cm)) {
-        state.last_reading_ms = AP_HAL::millis();
-        // update range_valid state based on distance measured
-        update_status();
-    } else if (AP_HAL::millis() - state.last_reading_ms > 200) {
-        set_status(RangeFinder::Status::NoData);
-    }
-}
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_uLanding.h b/libraries/AP_RangeFinder/AP_RangeFinder_uLanding.h
index 2cd6f6fd79..688d516dfa 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_uLanding.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_uLanding.h
@@ -10,9 +10,6 @@ public:
 
     using AP_RangeFinder_Backend_Serial::AP_RangeFinder_Backend_Serial;
 
-    // update state
-    void update(void) override;
-
 protected:
 
     MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
diff --git a/libraries/AP_RangeFinder/RangeFinder_Backend_Serial.cpp b/libraries/AP_RangeFinder/RangeFinder_Backend_Serial.cpp
index 30bc07f3c1..3a9b3e0e6b 100644
--- a/libraries/AP_RangeFinder/RangeFinder_Backend_Serial.cpp
+++ b/libraries/AP_RangeFinder/RangeFinder_Backend_Serial.cpp
@@ -62,7 +62,7 @@ void AP_RangeFinder_Backend_Serial::update(void)
         // update range_valid state based on distance measured
         state.last_reading_ms = AP_HAL::millis();
         update_status();
-    } else if (AP_HAL::millis() - state.last_reading_ms > 200) {
+    } else if (AP_HAL::millis() - state.last_reading_ms > read_timeout_ms()) {
         set_status(RangeFinder::Status::NoData);
     }
 }
diff --git a/libraries/AP_RangeFinder/RangeFinder_Backend_Serial.h b/libraries/AP_RangeFinder/RangeFinder_Backend_Serial.h
index 371ef77175..fb731db22c 100644
--- a/libraries/AP_RangeFinder/RangeFinder_Backend_Serial.h
+++ b/libraries/AP_RangeFinder/RangeFinder_Backend_Serial.h
@@ -30,4 +30,7 @@ protected:
     // it is essential that anyone relying on the base-class update to
     // implement this:
     virtual bool get_reading(uint16_t &reading_cm) { return 0; }
+
+    // maximum time between readings before we change state to NoData:
+    virtual uint16_t read_timeout_ms() const { return 200; }
 };