diff --git a/slsDetectorSoftware/multiSlsDetector/multiSlsDetector.cpp b/slsDetectorSoftware/multiSlsDetector/multiSlsDetector.cpp
index 030fe43a3..a4bc6f557 100644
--- a/slsDetectorSoftware/multiSlsDetector/multiSlsDetector.cpp
+++ b/slsDetectorSoftware/multiSlsDetector/multiSlsDetector.cpp
@@ -3220,7 +3220,18 @@ int multiSlsDetector::retrieveDetectorSetup(string const fname1, int level){
 
 
 int multiSlsDetector::testFunction(int times) {
-  return OK;
+
+	int ret=-100, ret1;
+	for (int idet=0; idet<thisMultiDetector->numberOfDetectors; idet++) {
+		if (detectors[idet]) {
+			ret1=detectors[idet]->testFunction(times);
+			if (ret==-100)
+				ret=ret1;
+			else if (ret!=ret1)
+				ret=-1;
+		}
+	}
+	return ret;
 }