diff --git a/selfdrive/controls/lib/longitudinal_planner.py b/selfdrive/controls/lib/longitudinal_planner.py
index 2b1fd01112..39450448fa 100755
--- a/selfdrive/controls/lib/longitudinal_planner.py
+++ b/selfdrive/controls/lib/longitudinal_planner.py
@@ -3,7 +3,7 @@ import math
 import numpy as np
 from openpilot.common.numpy_fast import clip, interp
 from openpilot.common.params import Params
-from cereal import log
+from cereal import car, log
 
 import cereal.messaging as messaging
 from openpilot.common.conversions import Conversions as CV
@@ -17,6 +17,8 @@ from openpilot.selfdrive.controls.lib.longitudinal_mpc_lib.long_mpc import T_IDX
 from openpilot.selfdrive.controls.lib.drive_helpers import V_CRUISE_MAX, CONTROL_N, get_speed_error
 from openpilot.common.swaglog import cloudlog
 
+ButtonType = car.CarState.ButtonEvent.Type
+
 LON_MPC_STEP = 0.2  # first step is 0.2s
 A_CRUISE_MIN = -1.2
 A_CRUISE_MAX_VALS = [1.6, 1.2, 0.8, 0.6]
@@ -89,8 +91,12 @@ class LongitudinalPlanner:
     return x, v, a, j
 
   def update(self, sm):
-    if self.param_read_counter % 50 == 0:
-      self.read_param()
+    # if self.param_read_counter % 50 == 0:
+    #   self.read_param()
+    # decrement personality on button press (Toyota can only decrement)
+    if any(not be.pressed and be.type == ButtonType.gapAdjustCruise for be in sm['carState'].buttonEvents):
+      self.personality = (self.personality - 1) % 3
+
     self.param_read_counter += 1
     self.mpc.mode = 'blended' if sm['controlsState'].experimentalMode else 'acc'