diff --git a/klippy/extras/pid_calibrate.py b/klippy/extras/pid_calibrate.py
index c7a731959..0cad07f50 100644
--- a/klippy/extras/pid_calibrate.py
+++ b/klippy/extras/pid_calibrate.py
@@ -9,20 +9,19 @@ import heaters
 class PIDCalibrate:
     def __init__(self, config):
         self.printer = config.get_printer()
-        self.gcode = self.printer.lookup_object('gcode')
-        self.gcode.register_command(
-            'PID_CALIBRATE', self.cmd_PID_CALIBRATE,
-            desc=self.cmd_PID_CALIBRATE_help)
+        gcode = self.printer.lookup_object('gcode')
+        gcode.register_command('PID_CALIBRATE', self.cmd_PID_CALIBRATE,
+                               desc=self.cmd_PID_CALIBRATE_help)
     cmd_PID_CALIBRATE_help = "Run PID calibration test"
-    def cmd_PID_CALIBRATE(self, params):
-        heater_name = self.gcode.get_str('HEATER', params)
-        target = self.gcode.get_float('TARGET', params)
-        write_file = self.gcode.get_int('WRITE_FILE', params, 0)
+    def cmd_PID_CALIBRATE(self, gcmd):
+        heater_name = gcmd.get('HEATER')
+        target = gcmd.get_float('TARGET')
+        write_file = gcmd.get_int('WRITE_FILE', 0)
         pheaters = self.printer.lookup_object('heaters')
         try:
             heater = pheaters.lookup_heater(heater_name)
         except self.printer.config_error as e:
-            raise self.gcode.error(str(e))
+            raise gcmd.error(str(e))
         self.printer.lookup_object('toolhead').get_last_move_time()
         calibrate = ControlAutoTune(heater, target)
         old_control = heater.set_control(calibrate)
@@ -38,7 +37,7 @@ class PIDCalibrate:
         # Log and report results
         Kp, Ki, Kd = calibrate.calc_final_pid()
         logging.info("Autotune: final: Kp=%f Ki=%f Kd=%f", Kp, Ki, Kd)
-        self.gcode.respond_info(
+        gcmd.respond_info(
             "PID parameters: pid_Kp=%.3f pid_Ki=%.3f pid_Kd=%.3f\n"
             "The SAVE_CONFIG command will update the printer config file\n"
             "with these parameters and restart the printer." % (Kp, Ki, Kd))