diff --git a/pipelines/LSSTCam-imSim/ApPipe.yaml b/pipelines/LSSTCam-imSim/ApPipe.yaml
index 434b950f..80a2f673 100644
--- a/pipelines/LSSTCam-imSim/ApPipe.yaml
+++ b/pipelines/LSSTCam-imSim/ApPipe.yaml
@@ -14,3 +14,4 @@ tasks:
     config:
       # Alert distribution only runnable in PP environment.
       alertPackager.doProduceAlerts: True
+      config.astrometry.referenceSelector.doUnresolved: False