diff --git a/src/gatt-client.c b/src/gatt-client.c
index 029a9d1..2af6979 100644
--- a/src/gatt-client.c
+++ b/src/gatt-client.c
@@ -309,7 +309,7 @@
 
 		if (err) {
 			reply = err > 0 ? create_gatt_dbus_error(msg, err) :
-				btd_error_failed(msg, strerror(err));
+				btd_error_failed(msg, strerror(-err));
 			goto send_reply;
 		}