diff --git a/y2019/control_loops/drivetrain/localizer.h b/y2019/control_loops/drivetrain/localizer.h
index f011720..3e20a1e 100644
--- a/y2019/control_loops/drivetrain/localizer.h
+++ b/y2019/control_loops/drivetrain/localizer.h
@@ -56,7 +56,7 @@
     if (t > HybridEkf::latest_t()) {
       LOG(ERROR,
           "target observations must be older than most recent encoder/gyro "
-          "update.");
+          "update.\n");
       return;
     }