diff --git a/libraries/AP_GPS/AP_GPS.cpp b/libraries/AP_GPS/AP_GPS.cpp
index 25058e3a10..8ab52caa71 100644
--- a/libraries/AP_GPS/AP_GPS.cpp
+++ b/libraries/AP_GPS/AP_GPS.cpp
@@ -464,7 +464,7 @@ bool AP_GPS::needs_uart(GPS_Type type) const
 }
 
 /// Startup initialisation.
-void AP_GPS::init(const AP_SerialManager& serial_manager)
+void AP_GPS::init()
 {
     // Set new primary param based on old auto_switch use second option
     if ((_auto_switch.get() == 3) && !_primary.configured()) {
@@ -473,6 +473,7 @@ void AP_GPS::init(const AP_SerialManager& serial_manager)
     }
 
     // search for serial ports with gps protocol
+    const auto &serial_manager = AP::serialmanager();
     uint8_t uart_idx = 0;
     for (uint8_t i=0; i<GPS_MAX_RECEIVERS; i++) {
         if (needs_uart((GPS_Type)_type[i].get())) {
diff --git a/libraries/AP_GPS/AP_GPS.h b/libraries/AP_GPS/AP_GPS.h
index 514c2b59d8..d5921f04c3 100644
--- a/libraries/AP_GPS/AP_GPS.h
+++ b/libraries/AP_GPS/AP_GPS.h
@@ -243,7 +243,7 @@ public:
     };
 
     /// Startup initialisation.
-    void init(const class AP_SerialManager& serial_manager);
+    void init();
 
     /// Update GPS state based on possible bytes received from the module.
     /// This routine must be called periodically (typically at 10Hz or
diff --git a/libraries/AP_GPS/examples/GPS_AUTO_test/GPS_AUTO_test.cpp b/libraries/AP_GPS/examples/GPS_AUTO_test/GPS_AUTO_test.cpp
index 8a4262fed9..278b0ee3e5 100644
--- a/libraries/AP_GPS/examples/GPS_AUTO_test/GPS_AUTO_test.cpp
+++ b/libraries/AP_GPS/examples/GPS_AUTO_test/GPS_AUTO_test.cpp
@@ -66,7 +66,7 @@ void setup()
 
     // Initialize the UART for GPS system
     serial_manager.init();
-    gps.init(serial_manager);
+    gps.init();
 }