diff --git a/libraries/AP_HAL_PX4/Scheduler.cpp b/libraries/AP_HAL_PX4/Scheduler.cpp
index a3a02f7e2e..96adc4cb5f 100644
--- a/libraries/AP_HAL_PX4/Scheduler.cpp
+++ b/libraries/AP_HAL_PX4/Scheduler.cpp
@@ -184,9 +184,7 @@ void PX4Scheduler::delay(uint16_t ms)
            !_px4_thread_should_exit) {
         delay_microseconds_semaphore(1000);
         if (_min_delay_cb_ms <= ms) {
-            if (_delay_cb) {
-                _delay_cb();
-            }
+            call_delay_cb();
         }
     }
     perf_end(_perf_delay);
@@ -195,13 +193,6 @@ void PX4Scheduler::delay(uint16_t ms)
     }
 }
 
-void PX4Scheduler::register_delay_callback(AP_HAL::Proc proc,
-                                            uint16_t min_time_ms)
-{
-    _delay_cb = proc;
-    _min_delay_cb_ms = min_time_ms;
-}
-
 void PX4Scheduler::register_timer_process(AP_HAL::MemberProc proc)
 {
     for (uint8_t i = 0; i < _num_timer_procs; i++) {
diff --git a/libraries/AP_HAL_PX4/Scheduler.h b/libraries/AP_HAL_PX4/Scheduler.h
index cc8989189e..a9b4f59df9 100644
--- a/libraries/AP_HAL_PX4/Scheduler.h
+++ b/libraries/AP_HAL_PX4/Scheduler.h
@@ -50,7 +50,6 @@ public:
     void     delay(uint16_t ms);
     void     delay_microseconds(uint16_t us);
     void     delay_microseconds_boost(uint16_t us);
-    void     register_delay_callback(AP_HAL::Proc, uint16_t min_time_ms);
     void     register_timer_process(AP_HAL::MemberProc);
     void     register_io_process(AP_HAL::MemberProc);
     void     register_timer_failsafe(AP_HAL::Proc, uint32_t period_us);