diff --git a/selfdrive/thermald.py b/selfdrive/thermald.py
index b866521a92..6a007558aa 100755
--- a/selfdrive/thermald.py
+++ b/selfdrive/thermald.py
@@ -157,6 +157,7 @@ def thermald_thread():
     # clear car params when panda gets disconnected
     if health is None and health_prev is not None:
       params.panda_disconnect()
+      ignition_seen = False
     health_prev = health
 
     # loggerd is gated based on free space