diff --git a/libraries/AP_RangeFinder/AP_RangeFinder.cpp b/libraries/AP_RangeFinder/AP_RangeFinder.cpp
index 16e8f089c1fa1..3be3b18b475b0 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder.cpp
@@ -241,6 +241,19 @@ void RangeFinder::update(void)
                 continue;
             }
             drivers[i]->update();
+
+            WITH_SEMAPHORE(drivers[i]->get_semaphore());
+            /*
+              ensure that all drivers timeout to NoData. If they are
+              currently in NotConnected state then leave it in that
+              state as they have never had any data
+             */
+            const uint32_t last_update_ms = drivers[i]->last_reading_ms();
+            const uint32_t now_ms = AP_HAL::millis();
+            if (state[i].status != Status::NotConnected &&
+                now_ms - last_update_ms > drivers[i]->read_timeout_ms()) {
+                state[i].status = Status::NoData;
+            }
         }
     }
 #if HAL_LOGGING_ENABLED
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.h b/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.h
index 04fccaae4e35e..dfe507d594d76 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_BLPing.h
@@ -180,7 +180,7 @@ class AP_RangeFinder_BLPing : public AP_RangeFinder_Backend_Serial
      *
      * @return uint16_t
      */
-    uint16_t read_timeout_ms() const override { return 1000; }
+    uint32_t read_timeout_ms() const override { return 1000; }
 
     /**
      * @brief system time that sensor was last initialised
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Backend.h b/libraries/AP_RangeFinder/AP_RangeFinder_Backend.h
index ca2decd044e30..16294d94bec51 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Backend.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Backend.h
@@ -79,6 +79,12 @@ class AP_RangeFinder_Backend
     // parameter value which may be changed at runtime.
     RangeFinder::Type allocated_type() const { return _backend_type; }
 
+    // maximum time between readings before we change state to NoData:
+    virtual uint32_t read_timeout_ms() const { return 200; }
+
+    // get reference to driver semaphore
+    HAL_Semaphore &get_semaphore(void) { return _sem; }
+
 protected:
 
     // update status based on distance measurement
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Backend_CAN.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_Backend_CAN.cpp
index 659a4af199106..494ff77dc7b7a 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Backend_CAN.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Backend_CAN.cpp
@@ -58,8 +58,6 @@ void AP_RangeFinder_Backend_CAN::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 >= read_timeout_ms()) {
-        set_status(RangeFinder::Status::NoData);
     }
 }
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Backend_CAN.h b/libraries/AP_RangeFinder/AP_RangeFinder_Backend_CAN.h
index 96d62aa94dedf..4d3b690f6a2e8 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Backend_CAN.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Backend_CAN.h
@@ -32,9 +32,6 @@ class AP_RangeFinder_Backend_CAN : public AP_RangeFinder_Backend
     // it is essential that anyone relying on the base-class update to implement this
     virtual bool handle_frame(AP_HAL::CANFrame &frame) = 0;
 
-    // maximum time between readings before we change state to NoData:
-    virtual uint32_t read_timeout_ms() const { return 200; }
-
     virtual MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
         return MAV_DISTANCE_SENSOR_RADAR;
     }
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Backend_Serial.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_Backend_Serial.cpp
index af27aaf5a7ad4..913d58e2b3a89 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Backend_Serial.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Backend_Serial.cpp
@@ -57,7 +57,5 @@ 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 > read_timeout_ms()) {
-        set_status(RangeFinder::Status::NoData);
     }
 }
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Backend_Serial.h b/libraries/AP_RangeFinder/AP_RangeFinder_Backend_Serial.h
index e4349d75b8a8f..1219028829bf9 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Backend_Serial.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Backend_Serial.h
@@ -34,7 +34,4 @@ class AP_RangeFinder_Backend_Serial : public AP_RangeFinder_Backend
     // Like get_reading() this method is called in the base-class update() method.
     virtual int8_t get_signal_quality_pct() const WARN_IF_UNUSED
     { return RangeFinder::SIGNAL_QUALITY_UNKNOWN; }
-
-    // maximum time between readings before we change state to NoData:
-    virtual uint16_t read_timeout_ms() const { return 200; }
 };
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Benewake_TFMiniPlus.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_Benewake_TFMiniPlus.cpp
index fc4e227c74b05..bfa2d597322e8 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Benewake_TFMiniPlus.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Benewake_TFMiniPlus.cpp
@@ -148,8 +148,6 @@ void AP_RangeFinder_Benewake_TFMiniPlus::update()
         accum.sum = 0;
         accum.count = 0;
         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_DroneCAN.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_DroneCAN.cpp
index 4db29571beda1..49ee91b4a8390 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_DroneCAN.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_DroneCAN.cpp
@@ -84,10 +84,7 @@ AP_RangeFinder_DroneCAN* AP_RangeFinder_DroneCAN::get_dronecan_backend(AP_DroneC
 void AP_RangeFinder_DroneCAN::update()
 {
     WITH_SEMAPHORE(_sem);
-    if ((AP_HAL::millis() - _last_reading_ms) > 500) {
-        //if data is older than 500ms, report NoData
-        set_status(RangeFinder::Status::NoData);
-    } else if (_status == RangeFinder::Status::Good && new_data) {
+    if (_status == RangeFinder::Status::Good && new_data) {
         //copy over states
         state.distance_m = _distance_cm * 0.01f;
         state.last_reading_ms = _last_reading_ms;
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_DroneCAN.h b/libraries/AP_RangeFinder/AP_RangeFinder_DroneCAN.h
index 6d763b2b97fba..a5f3beaac2f39 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_DroneCAN.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_DroneCAN.h
@@ -22,6 +22,9 @@ class AP_RangeFinder_DroneCAN : public AP_RangeFinder_Backend {
 
     static void handle_measurement(AP_DroneCAN *ap_dronecan, const CanardRxTransfer& transfer, const uavcan_equipment_range_sensor_Measurement &msg);
 
+    // maximum time between readings before we change state to NoData:
+    uint32_t read_timeout_ms() const override { return 500; }
+
 protected:
     virtual MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
         return _sensor_type;
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_HC_SR04.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_HC_SR04.cpp
index 6e7cc156ec47a..17af4e3a74734 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_HC_SR04.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_HC_SR04.cpp
@@ -97,13 +97,7 @@ void AP_RangeFinder_HC_SR04::update(void)
     const uint32_t value_us = pwm_source.get_pwm_us();
 
     const uint32_t now = AP_HAL::millis();
-    if (value_us == 0) {
-        // no reading; check for timeout:
-        if (now - last_reading_ms > 1000) {
-            // no reading for a second - something is broken
-            state.distance_m = 0.0f;
-        }
-    } else {
+    if (value_us != 0) {
         // gcs().send_text(MAV_SEVERITY_WARNING, "Pong!");
         // a new reading - convert time to distance
         state.distance_m = (value_us * (1.0/58.0f)) * 0.01f;  // 58 is from datasheet, mult for performance
@@ -126,10 +120,10 @@ void AP_RangeFinder_HC_SR04::update(void)
         }
 
         last_reading_ms = now;
-    }
 
-    // update range_valid state based on distance measured
-    update_status();
+        // update range_valid state based on distance measured
+        update_status();
+    }
 
     // consider sending new ping
     if (now - last_ping_ms > 67) { // read ~@15Hz - recommended 60ms delay from datasheet
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_LeddarVu8.h b/libraries/AP_RangeFinder/AP_RangeFinder_LeddarVu8.h
index 68db11394ebc3..ce0459019c73f 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_LeddarVu8.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_LeddarVu8.h
@@ -36,7 +36,7 @@ class AP_RangeFinder_LeddarVu8 : public AP_RangeFinder_Backend_Serial
     bool get_reading(float &reading_m) override;
 
     // maximum time between readings before we change state to NoData:
-    uint16_t read_timeout_ms() const override { return 500; }
+    uint32_t read_timeout_ms() const override { return 500; }
 
 private:
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_LightWareI2C.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_LightWareI2C.cpp
index 725b76f4f63ad..47f454f029af4 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_LightWareI2C.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_LightWareI2C.cpp
@@ -465,21 +465,23 @@ void AP_RangeFinder_LightWareI2C::update(void)
 
 void AP_RangeFinder_LightWareI2C::legacy_timer(void)
 {
-    if (legacy_get_reading(state.distance_m)) {
+    float distance_m = 0;
+    if (legacy_get_reading(distance_m)) {
         // update range_valid state based on distance measured
+        WITH_SEMAPHORE(_sem);
+        state.distance_m = distance_m;
         update_status();
-    } else {
-        set_status(RangeFinder::Status::NoData);
     }
 }
 
 void AP_RangeFinder_LightWareI2C::sf20_timer(void)
 {
-    if (sf20_get_reading(state.distance_m)) {
+    float distance_m = 0;
+    if (sf20_get_reading(distance_m)) {
         // update range_valid state based on distance measured
+        WITH_SEMAPHORE(_sem);
+        state.distance_m = distance_m;
         update_status();
-    } else {
-        set_status(RangeFinder::Status::NoData);
     }
 }
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Lua.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_Lua.cpp
index 75e22b2aaba5f..8a56f82292c81 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Lua.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Lua.cpp
@@ -48,16 +48,11 @@ bool AP_RangeFinder_Lua::handle_script_msg(float dist_m) {
 
     WITH_SEMAPHORE(_sem);
 
-    // Time out on incoming data; if we don't get new data in 500ms, dump it
-    if (now - _state_pending.last_reading_ms > AP_RANGEFINDER_LUA_TIMEOUT_MS) {
-        set_status(_state_pending, RangeFinder::Status::NoData);
-    } else {
-        _state_pending.last_reading_ms = now;
-        _state_pending.distance_m = dist_m;
-        _state_pending.signal_quality_pct = RangeFinder::SIGNAL_QUALITY_UNKNOWN;
-        _state_pending.voltage_mv = 0;
-        update_status(_state_pending);
-    }
+    _state_pending.last_reading_ms = now;
+    _state_pending.distance_m = dist_m;
+    _state_pending.signal_quality_pct = RangeFinder::SIGNAL_QUALITY_UNKNOWN;
+    _state_pending.voltage_mv = 0;
+    update_status(_state_pending);
 
     return true;
 }
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Lua.h b/libraries/AP_RangeFinder/AP_RangeFinder_Lua.h
index 0bd7f7a1acb6b..dc3208497f3a8 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Lua.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Lua.h
@@ -27,6 +27,9 @@ class AP_RangeFinder_Lua : public AP_RangeFinder_Backend
         return MAV_DISTANCE_SENSOR_UNKNOWN;
     }
 
+    // maximum time between readings before we change state to NoData:
+    uint32_t read_timeout_ms() const override { return AP_RANGEFINDER_LUA_TIMEOUT_MS; }
+    
 private:
 
     RangeFinder::RangeFinder_State _state_pending = {};
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_MAVLink.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_MAVLink.cpp
index b4fc5fb1ff597..cbefdb3dae98b 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_MAVLink.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_MAVLink.cpp
@@ -42,6 +42,10 @@ void AP_RangeFinder_MAVLink::handle_msg(const mavlink_message_t &msg)
             // Map 1 to 0 as that is what ardupilot uses as the worst signal quality
             signal_quality = RangeFinder::SIGNAL_QUALITY_MIN;
         }
+        WITH_SEMAPHORE(_sem);
+        state.distance_m = distance_cm * 0.01f;
+        state.signal_quality_pct = signal_quality;
+        update_status();
     }
 }
 
@@ -69,22 +73,4 @@ int16_t AP_RangeFinder_MAVLink::min_distance_cm() const
     return _min_distance_cm;
 }
 
-/*
-   update the state of the sensor
-*/
-void AP_RangeFinder_MAVLink::update(void)
-{
-    //Time out on incoming data; if we don't get new
-    //data in 500ms, dump it
-    if (AP_HAL::millis() - state.last_reading_ms > AP_RANGEFINDER_MAVLINK_TIMEOUT_MS) {
-        set_status(RangeFinder::Status::NoData);
-        state.distance_m = 0.0f;
-        state.signal_quality_pct = RangeFinder::SIGNAL_QUALITY_UNKNOWN;
-    } else {
-        state.distance_m = distance_cm * 0.01f;
-        state.signal_quality_pct = signal_quality;
-        update_status();
-    }
-}
-
 #endif
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_MAVLink.h b/libraries/AP_RangeFinder/AP_RangeFinder_MAVLink.h
index 47cd080c13f9a..8e3b268b83320 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_MAVLink.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_MAVLink.h
@@ -22,8 +22,8 @@ class AP_RangeFinder_MAVLink : public AP_RangeFinder_Backend
     // there is an attached MAVLink rangefinder
     static bool detect() { return true; }
 
-    // update state
-    void update(void) override;
+    // empty update
+    void update(void) override {}
 
     // Get update from mavlink
     void handle_msg(const mavlink_message_t &msg) override;
@@ -31,6 +31,8 @@ class AP_RangeFinder_MAVLink : public AP_RangeFinder_Backend
     int16_t max_distance_cm() const override;
     int16_t min_distance_cm() const override;
 
+    uint32_t read_timeout_ms() const override { return AP_RANGEFINDER_MAVLINK_TIMEOUT_MS; }
+
 protected:
 
     MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_MSP.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_MSP.cpp
index e5ee32bdc5a39..26f188c70e289 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_MSP.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_MSP.cpp
@@ -29,7 +29,6 @@ AP_RangeFinder_MSP::AP_RangeFinder_MSP(RangeFinder::RangeFinder_State &_state, A
     AP_RangeFinder_Backend(_state, _params)
 {
     state.last_reading_ms = AP_HAL::millis();
-    distance_cm = 0;
 }
 
 /*
@@ -48,24 +47,10 @@ bool AP_RangeFinder_MSP::detect()
 */
 void AP_RangeFinder_MSP::handle_msp(const MSP::msp_rangefinder_data_message_t &pkt)
 {
+    WITH_SEMAPHORE(_sem);
+    state.distance_m = pkt.distance_mm * 0.001f;
     state.last_reading_ms = AP_HAL::millis();
-    distance_cm = pkt.distance_mm / 10;
-}
-
-/*
-   update the state of the sensor
-*/
-void AP_RangeFinder_MSP::update(void)
-{
-    //Time out on incoming data; if we don't get new
-    //data in 500ms, dump it
-    if (AP_HAL::millis() - state.last_reading_ms > AP_RANGEFINDER_MSP_TIMEOUT_MS) {
-        set_status(RangeFinder::Status::NoData);
-        state.distance_m = 0.0f;
-    } else {
-        state.distance_m = distance_cm * 0.01f;
-        update_status();
-    }
+    update_status();
 }
 
 #endif //HAL_MSP_RANGEFINDER_ENABLED
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_MSP.h b/libraries/AP_RangeFinder/AP_RangeFinder_MSP.h
index 59643fe69684e..688b2477d3967 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_MSP.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_MSP.h
@@ -20,12 +20,14 @@ class AP_RangeFinder_MSP : public AP_RangeFinder_Backend
     // static detection function
     static bool detect();
 
-    // update state
-    void update(void) override;
+    // empty update
+    void update(void) override {}
 
     // Get update from msp
     void handle_msp(const MSP::msp_rangefinder_data_message_t &pkt) override;
 
+    uint32_t read_timeout_ms() const override { return AP_RANGEFINDER_MSP_TIMEOUT_MS; }
+
 protected:
 
     MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
@@ -33,8 +35,6 @@ class AP_RangeFinder_MSP : public AP_RangeFinder_Backend
     }
 
 private:
-    uint16_t distance_cm;
-
     // start a reading
     static bool start_reading(void);
     static bool get_reading(uint16_t &reading_cm);
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.cpp
index 1cb7cdc5af66b..e387ccc026556 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.cpp
@@ -148,9 +148,6 @@ void AP_RangeFinder_MaxsonarI2CXL::update(void)
         state.distance_m = distance * 0.01f;
         new_distance = false;
         update_status();
-    } else if (AP_HAL::millis() - state.last_reading_ms > 300) {
-        // if no updates for 0.3 seconds set no-data
-        set_status(RangeFinder::Status::NoData);
     }
 }
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.h b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.h
index 7648133963f8d..0c07284a90c05 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.h
@@ -23,6 +23,8 @@ class AP_RangeFinder_MaxsonarI2CXL : public AP_RangeFinder_Backend
     // update state
     void update(void) override;
 
+    uint32_t read_timeout_ms() const override { return 300; }
+
 protected:
 
     MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.h b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.h
index b0693c11e3247..46a8e437b75b6 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarSerialLV.h
@@ -31,7 +31,7 @@ class AP_RangeFinder_MaxsonarSerialLV : public AP_RangeFinder_Backend_Serial
     // get a reading
     bool get_reading(float &reading_m) override;
 
-    uint16_t read_timeout_ms() const override { return 500; }
+    uint32_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.h b/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.h
index d8c7ff3d14520..f847f5ffc83e2 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_NMEA.h
@@ -58,7 +58,7 @@ class AP_RangeFinder_NMEA : public AP_RangeFinder_Backend_Serial
     // get temperature reading in C.  returns true on success and populates temp argument
     bool get_temp(float &temp) const override;
 
-    uint16_t read_timeout_ms() const override { return 3000; }
+    uint32_t read_timeout_ms() const override { return 3000; }
 
     // add a single character to the buffer and attempt to decode
     // returns true if a distance was successfully decoded
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_NRA24_CAN.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_NRA24_CAN.cpp
index 30f170adddc9d..9a6092b28f52e 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_NRA24_CAN.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_NRA24_CAN.cpp
@@ -14,15 +14,6 @@ void AP_RangeFinder_NRA24_CAN::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 > read_timeout_ms()) {
-        if (AP_HAL::millis() - last_heartbeat_ms > read_timeout_ms()) {
-            // no heartbeat, must be disconnected
-            set_status(RangeFinder::Status::NotConnected);
-        } else {
-            // Have heartbeat, just no data. Probably because this sensor doesn't output data when there is no relative motion infront of the radar.
-            // This case has special pre-arm check handling
-            set_status(RangeFinder::Status::NoData);
-        }
     }
 }
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_PWM.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_PWM.cpp
index 97352b2d4a83b..03eda44cd89d5 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_PWM.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_PWM.cpp
@@ -114,9 +114,6 @@ void AP_RangeFinder_PWM::update(void)
 
     if (!get_reading(state.distance_m)) {
         // failure; consider changing our state
-        if (AP_HAL::millis() - state.last_reading_ms > 200) {
-            set_status(RangeFinder::Status::NoData);
-        }
         return;
     }
     // add offset
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_PulsedLightLRF.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_PulsedLightLRF.cpp
index 5c9cbb38a9a2a..ac5b8a2e6973d 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_PulsedLightLRF.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_PulsedLightLRF.cpp
@@ -96,8 +96,6 @@ void AP_RangeFinder_PulsedLightLRF::timer(void)
             state.distance_m = filter.apply(_distance_cm*0.01);
             state.last_reading_ms = AP_HAL::millis();
             update_status();
-        } else if (AP_HAL::millis() - state.last_reading_ms > 200) {
-            set_status(RangeFinder::Status::NoData);
         }
         if (!v2_hardware) {
             // for v2 hw we use continuous mode
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_SITL.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_SITL.cpp
index a4e5f30493b20..dd7a214ef51dd 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_SITL.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_SITL.cpp
@@ -36,7 +36,6 @@ void AP_RangeFinder_SITL::update(void)
 
     // nan distance means nothing is connected
     if (isnan(dist) || isinf(dist)) {
-        state.status = RangeFinder::Status::NoData;
         return;
     }
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_TOFSenseF_I2C.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_TOFSenseF_I2C.cpp
index 55f0e497d62f0..40017e754ac05 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_TOFSenseF_I2C.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_TOFSenseF_I2C.cpp
@@ -150,9 +150,6 @@ void AP_RangeFinder_TOFSenseF_I2C::update(void)
         state.distance_m = distance_mm * 0.001f;
         new_distance = false;
         update_status();
-    } else if (AP_HAL::millis() - state.last_reading_ms > 300) {
-        // if no updates for 0.3 seconds set no-data
-        set_status(RangeFinder::Status::NoData);
     }
 }
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_TOFSenseF_I2C.h b/libraries/AP_RangeFinder/AP_RangeFinder_TOFSenseF_I2C.h
index 7f72f13108712..6623fe93de6c7 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_TOFSenseF_I2C.h
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_TOFSenseF_I2C.h
@@ -22,6 +22,8 @@ class AP_RangeFinder_TOFSenseF_I2C : public AP_RangeFinder_Backend
     // update state
     void update(void) override;
 
+    uint32_t read_timeout_ms() const override { return 300; }
+
 protected:
 
     MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override {
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_TeraRangerI2C.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_TeraRangerI2C.cpp
index c1772bfbad1f9..438714334e10e 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_TeraRangerI2C.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_TeraRangerI2C.cpp
@@ -187,8 +187,6 @@ void AP_RangeFinder_TeraRangerI2C::update(void)
         accum.sum = 0;
         accum.count = 0;
         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_VL53L0X.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_VL53L0X.cpp
index 51c10dec8cd00..bedc5087ff0a2 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_VL53L0X.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_VL53L0X.cpp
@@ -763,21 +763,21 @@ uint16_t AP_RangeFinder_VL53L0X::read_register16(uint8_t reg)
 */
 void AP_RangeFinder_VL53L0X::update(void)
 {
+    WITH_SEMAPHORE(_sem);
     if (counter > 0) {
         state.distance_m = (sum_mm * 0.001f) / counter;
         state.last_reading_ms = AP_HAL::millis();
         sum_mm = 0;
         counter = 0;
         update_status();
-    } else {
-        set_status(RangeFinder::Status::NoData);
     }
 }
 
 void AP_RangeFinder_VL53L0X::timer(void)
 {
-    uint16_t range_mm;
+     uint16_t range_mm;
     if (get_reading(range_mm) && range_mm < 8000) {
+        WITH_SEMAPHORE(_sem);
         sum_mm += range_mm;
         counter++;
     }
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_VL53L1X.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_VL53L1X.cpp
index e0eba359eee8f..1ed8425116095 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_VL53L1X.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_VL53L1X.cpp
@@ -575,9 +575,6 @@ void AP_RangeFinder_VL53L1X::update(void)
         update_status();
         sum_mm = 0;
         counter = 0;
-    } else if (AP_HAL::millis() - state.last_reading_ms > 200) {
-        // if no updates for 0.2s set no-data
-        set_status(RangeFinder::Status::NoData);
     }
 }
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_Wasp.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_Wasp.cpp
index 5885b2af14625..0fddcd994b8de 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_Wasp.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_Wasp.cpp
@@ -131,9 +131,7 @@ bool AP_RangeFinder_Wasp::get_reading(float &reading_m) {
 #define COMMAND_BUFFER_LEN 15
 
 void AP_RangeFinder_Wasp::update(void) {
-    if (!get_reading(state.distance_m)) {
-        set_status(RangeFinder::Status::NoData);
-    }
+    get_reading(state.distance_m);
 
     if (AP_HAL::millis() - state.last_reading_ms > 500) {
         // attempt to reconfigure on the assumption this was a bad baud setting