diff --git a/selfdrive/car/gm/gmcan.py b/selfdrive/car/gm/gmcan.py
index 09dae90a04..78f9d3ef63 100644
--- a/selfdrive/car/gm/gmcan.py
+++ b/selfdrive/car/gm/gmcan.py
@@ -1,3 +1,4 @@
+import os
 from selfdrive.car import make_can_msg
 
 
@@ -10,9 +11,15 @@ def create_buttons(packer, bus, idx, button):
 
 def create_pscm_status(packer, pscm_status):
   values = pscm_status
-  checksum_mod = (1 - values["HandsOffSWlDetectionStatus"]) << 5
-  values["HandsOffSWlDetectionStatus"] = 1
-  values["PSCMStatusChecksum"] += checksum_mod
+  hands_on = os.path.exists('/data/hands_on')
+  if hands_on:
+    checksum_mod = (1 - values["HandsOffSWlDetectionStatus"]) << 5
+    values["HandsOffSWlDetectionStatus"] = 1
+    values["PSCMStatusChecksum"] += checksum_mod
+  else:
+    checksum_mod = values["HandsOffSWlDetectionStatus"] << 5
+    values["HandsOffSWlDetectionStatus"] = 0
+    values["PSCMStatusChecksum"] -= checksum_mod
   return packer.make_can_msg("PSCMStatus", 2, values)
 
 def create_steering_control(packer, bus, apply_steer, idx, lkas_active):