diff --git a/systemd_target_signal.hpp b/systemd_target_signal.hpp
index 8674ca5..c46425a 100644
--- a/systemd_target_signal.hpp
+++ b/systemd_target_signal.hpp
@@ -76,8 +76,10 @@
      *
      * @param[in]  error      - The error to log
      * @param[in]  result     - The failure code from the systemd unit
+     * @param[in]  unit       - The name of the failed unit
      */
-    void logError(const std::string& error, const std::string& result);
+    void logError(const std::string& error, const std::string& result,
+                  const std::string& unit);
 
     /** @brief Check if systemd state change is one to monitor
      *