diff --git a/src/net/nl_wifi_sm.c b/src/net/nl_wifi_sm.c
index e606d49..ff653be 100644
--- a/src/net/nl_wifi_sm.c
+++ b/src/net/nl_wifi_sm.c
@@ -240,6 +240,12 @@ nl_wifi_actions_t nl_wifi_sm_standalone(nl_wifi_sm_t *sm, bool pulse, uint32_t n
         sm->pulse_armed = true;
         sm->pulse_stop_at = now + NL_WIFI_STANDALONE_PULSE_MS;
         a.pulse_on = true;
+    } else if (sm->pulsing) {
+        /* Ein laufender unbefristeter Puls (aus dem Onboarding-AP) hat im eigenen AP keinen
+         * Timer mehr, der ihn beendet; er uebermalte dauerhaft die normale Ausgabe. */
+        sm->pulsing = false;
+        sm->pulse_armed = false;
+        a.pulse_off = true;
     }
     return a;
 }
diff --git a/test/test_wifi_sm.c b/test/test_wifi_sm.c
index c75a1be..009f675 100644
--- a/test/test_wifi_sm.c
+++ b/test/test_wifi_sm.c
@@ -307,6 +307,9 @@ static void test_failed_onboarding_returns_to_standalone(void)
     TEST_ASSERT_TRUE(sm.standalone);
     TEST_ASSERT_FALSE(nl_wifi_sm_open_access(&sm));
     TEST_ASSERT_FALSE(a.clear_standalone);
+    TEST_ASSERT_FALSE(a.connect);
+    TEST_ASSERT_TRUE(a.disconnect);
+    TEST_ASSERT_TRUE(a.start_ap);
     TEST_ASSERT_EQUAL(NL_WIFI_ERR_AUTH, sm.error);
 }
 
@@ -315,9 +318,13 @@ static void test_onboarding_timeout_returns_to_standalone(void)
 {
     nl_wifi_sm_start(&sm, false, true, false, 0);
     nl_wifi_sm_onboard(&sm, 1000);
-    nl_wifi_sm_tick(&sm, 1000 + NL_WIFI_ONBOARD_TIMEOUT_MS);
+    a = nl_wifi_sm_tick(&sm, 1000 + NL_WIFI_ONBOARD_TIMEOUT_MS);
     TEST_ASSERT_EQUAL(NL_WIFI_ST_STANDALONE, sm.state);
     TEST_ASSERT_EQUAL(NL_WIFI_ERR_TIMEOUT, sm.error);
+    TEST_ASSERT_FALSE(a.connect);
+    TEST_ASSERT_TRUE(a.disconnect);
+    TEST_ASSERT_TRUE(a.start_ap);
+    TEST_ASSERT_FALSE(nl_wifi_sm_open_access(&sm));
 }
 
 /* Der bisherige Weg bleibt unberuehrt: ohne Standalone und ohne gespeicherte Daten
@@ -351,6 +358,8 @@ static void test_leaving_standalone_with_credentials_connects(void)
     nl_wifi_sm_start(&sm, true, true, false, 0);
     a = nl_wifi_sm_leave_standalone(&sm, true, 1000);
     TEST_ASSERT_TRUE(a.connect);
+    TEST_ASSERT_FALSE(a.start_ap);
+    TEST_ASSERT_FALSE(nl_wifi_sm_open_access(&sm));
     TEST_ASSERT_FALSE(sm.standalone);
     TEST_ASSERT_EQUAL(NL_WIFI_ST_STA_CONNECTING, sm.state);
 }
@@ -382,6 +391,68 @@ static void test_onboard_cancels_running_start_pulse(void)
     TEST_ASSERT_FALSE(nl_wifi_sm_tick(&sm, 20000).pulse_off);
 }
 
+/* Der eigentliche Spec-Fall: gespeicherte Zugangsdaten UND Standalone, der Test scheitert.
+ * Die Lampe darf nicht in den Rueckfall (APSTA_FALLBACK) mit den alten Daten gehen und
+ * damit ihren eigenen AP verlassen, sondern bleibt im Standalone-AP. */
+static void test_failed_onboarding_with_credentials_stays_standalone(void)
+{
+    nl_wifi_sm_start(&sm, true, true, false, 0);
+    nl_wifi_sm_onboard(&sm, 1000);
+    a = nl_wifi_sm_event(&sm, NL_WIFI_EV_JOIN_FAILED, NL_WIFI_ERR_AUTH, 2000);
+    TEST_ASSERT_EQUAL(NL_WIFI_ST_STANDALONE, sm.state);
+    TEST_ASSERT_FALSE(a.connect);
+    TEST_ASSERT_TRUE(a.disconnect);
+    TEST_ASSERT_TRUE(a.start_ap);
+    TEST_ASSERT_FALSE(nl_wifi_sm_open_access(&sm));
+}
+
+static void test_onboarding_timeout_with_credentials_stays_standalone(void)
+{
+    nl_wifi_sm_start(&sm, true, true, false, 0);
+    nl_wifi_sm_onboard(&sm, 1000);
+    a = nl_wifi_sm_tick(&sm, 1000 + NL_WIFI_ONBOARD_TIMEOUT_MS);
+    TEST_ASSERT_EQUAL(NL_WIFI_ST_STANDALONE, sm.state);
+    TEST_ASSERT_FALSE(a.connect);
+    TEST_ASSERT_TRUE(a.disconnect);
+    TEST_ASSERT_FALSE(nl_wifi_sm_open_access(&sm));
+}
+
+/* Nach gelungenem Onboarding laeuft noch der AP-Stopptimer. Schaltet man jetzt auf
+ * Standalone, muss er weg sein, sonst schaltet tick() den AP ab und die Lampe ist
+ * ueber nichts mehr erreichbar. */
+static void test_standalone_cancels_pending_ap_stop(void)
+{
+    nl_wifi_sm_start(&sm, false, false, false, 0);
+    nl_wifi_sm_onboard(&sm, 1000);
+    nl_wifi_sm_event(&sm, NL_WIFI_EV_CONNECTED, NL_WIFI_ERR_NONE, 2000);
+    nl_wifi_sm_standalone(&sm, false, 3000);
+    a = nl_wifi_sm_tick(&sm, 2000 + NL_WIFI_AP_CLOSE_ONBOARD_MS);
+    TEST_ASSERT_FALSE(a.stop_ap);
+    TEST_ASSERT_TRUE(sm.ap_up);
+}
+
+/* Ein unbefristeter Puls aus dem Onboarding-AP muss beim Wechsel ohne Puls enden, denn
+ * im Standalone-Modus gibt es keinen Timer mehr, der ihn beendete. */
+static void test_standalone_without_pulse_ends_running_pulse(void)
+{
+    nl_wifi_sm_start(&sm, false, false, false, 0);
+    TEST_ASSERT_TRUE(sm.pulsing);
+    a = nl_wifi_sm_standalone(&sm, false, 1000);
+    TEST_ASSERT_TRUE(a.pulse_off);
+    TEST_ASSERT_FALSE(a.pulse_on);
+    TEST_ASSERT_FALSE(sm.pulsing);
+    TEST_ASSERT_FALSE(nl_wifi_sm_tick(&sm, 1000 + NL_WIFI_STANDALONE_PULSE_MS).pulse_off);
+}
+
+/* onboard() aus dem Onboarding-AP laesst den unbefristeten Puls in Ruhe. */
+static void test_onboard_from_ap_onboarding_keeps_pulse(void)
+{
+    nl_wifi_sm_start(&sm, false, false, false, 0);
+    a = nl_wifi_sm_onboard(&sm, 1000);
+    TEST_ASSERT_FALSE(a.pulse_off);
+    TEST_ASSERT_TRUE(sm.pulsing);
+}
+
 int main(void)
 {
     UNITY_BEGIN();
@@ -414,5 +485,10 @@ int main(void)
     RUN_TEST(test_leaving_standalone_with_credentials_connects);
     RUN_TEST(test_leaving_standalone_without_credentials_opens_onboarding);
     RUN_TEST(test_onboard_cancels_running_start_pulse);
+    RUN_TEST(test_failed_onboarding_with_credentials_stays_standalone);
+    RUN_TEST(test_onboarding_timeout_with_credentials_stays_standalone);
+    RUN_TEST(test_standalone_cancels_pending_ap_stop);
+    RUN_TEST(test_standalone_without_pulse_ends_running_pulse);
+    RUN_TEST(test_onboard_from_ap_onboarding_keeps_pulse);
     return UNITY_END();
 }