diff --git a/plugins/quectel.c b/plugins/quectel.c
index dea23bdd..d4947489 100644
--- a/plugins/quectel.c
+++ b/plugins/quectel.c
@@ -84,15 +84,22 @@ enum quectel_model {
 	QUECTEL_MC60,
 };
 
+enum quectel_state {
+	QUECTEL_STATE_INITIALIZING = 0,
+	QUECTEL_STATE_POST_SIM,
+	QUECTEL_STATE_READY,
+	QUECTEL_STATE_INITIALIZED,
+};
+
 struct quectel_data {
 	GAtChat *modem;
 	GAtChat *aux;
-	guint cpin_ready;
-	guint call_ready;
-	bool have_sim;
 	enum ofono_vendor vendor;
 	enum quectel_model model;
-	struct l_timeout *sms_ready_timer;
+	enum quectel_state state;
+	struct ofono_sim *sim;
+	enum ofono_sim_state sim_state;
+	unsigned int sim_watch;
 
 	/* used by quectel uart driver */
 	GAtChat *uart;
@@ -185,9 +192,6 @@ static void quectel_remove(struct ofono_modem *modem)
 
 	DBG("%p", modem);
 
-	if (data->cpin_ready != 0)
-		g_at_chat_unregister(data->aux, data->cpin_ready);
-
 	ofono_modem_set_data(modem, NULL);
 	l_timeout_remove(data->init_timeout);
 	l_gpio_writer_free(data->gpio);
@@ -527,42 +531,211 @@ static void dbus_hw_enable(struct ofono_modem *modem)
 	ofono_modem_add_interface(modem, dbus_hw_interface);
 }
 
-static void cpin_notify(GAtResult *result, gpointer user_data)
+static void qinistat_cb(gboolean ok, GAtResult *result, gpointer user_data)
 {
 	struct ofono_modem *modem = user_data;
 	struct quectel_data *data = ofono_modem_get_data(modem);
-	const char *sim_inserted;
 	GAtResultIter iter;
+	int ready = 0;
+	int status;
 
 	DBG("%p", modem);
 
 	g_at_result_iter_init(&iter, result);
 
-	if (!g_at_result_iter_next(&iter, "+CPIN:"))
+	if (!g_at_result_iter_next(&iter, "+QINISTAT:"))
 		return;
 
-	g_at_result_iter_next_unquoted_string(&iter, &sim_inserted);
+	if (!g_at_result_iter_next_number(&iter, &status))
+		return;
 
-	if (g_strcmp0(sim_inserted, "NOT INSERTED") != 0)
-		data->have_sim = true;
+	DBG("qinistat: %d", status);
 
-	ofono_modem_set_powered(modem, TRUE);
+	switch (data->model) {
+	case QUECTEL_UC15:
+		/* UC15 uses a bitmap of 1 + 2 + 4 = 7 */
+		ready = 7;
+		break;
+	case QUECTEL_M95:
+	case QUECTEL_MC60:
+		/* M95 and MC60 uses a counter to 3 */
+		ready = 3;
+		break;
+	case QUECTEL_UNKNOWN:
+		ready = 0;
+		break;
+	}
 
-	/* Turn off the radio. */
-	g_at_chat_send(data->aux, "AT+CFUN=4", none_prefix, NULL, NULL, NULL);
+	if (status != ready) {
+		l_timeout_modify_ms(data->init_timeout, 500);
+		return;
+	}
 
-	g_at_chat_unregister(data->aux, data->cpin_ready);
-	data->cpin_ready = 0;
+	l_timeout_remove(data->init_timeout);
+	data->init_timeout = NULL;
 
-	dbus_hw_enable(modem);
+	if (data->sim_state == OFONO_SIM_STATE_READY) {
+		/*
+		 * when initializing with a non-locked sim card, the sim atom
+		 * isn't created until now to avoid accessing it before the
+		 * modem is ready.
+		 *
+		 * call ofono_modem_set_powered() to make ofono call
+		 * quectel_pre_sim() where the sim atom is created.
+		 */
+		ofono_modem_set_powered(modem, true);
+	} else {
+		/*
+		 * When initialized with a locked sim card, the modem is already
+		 * powered up, and the inserted signal has been sent to allow
+		 * the pin to be entered. So simply update the state, and notify
+		 * about the finished initialization below.
+		 */
+		data->sim_state = OFONO_SIM_STATE_READY;
+	}
+
+	ofono_sim_initialized_notify(data->sim);
+
+	/*
+	 * If quectel_post_sim() has not yet been called, then postpone atom
+	 * creation until it is called. Otherwise create the atoms now.
+	 */
+	if (data->state != QUECTEL_STATE_POST_SIM) {
+		data->state = QUECTEL_STATE_READY;
+		return;
+	}
+
+	ofono_sms_create(modem, data->vendor, "atmodem", data->aux);
+	ofono_phonebook_create(modem, data->vendor, "atmodem", data->aux);
+	ofono_voicecall_create(modem, data->vendor, "atmodem", data->aux);
+	ofono_call_volume_create(modem, data->vendor, "atmodem", data->aux);
+	data->state = QUECTEL_STATE_INITIALIZED;
+}
+
+static void init_timer_cb(struct l_timeout *timeout, void *user_data)
+{
+	struct ofono_modem *modem = user_data;
+	struct quectel_data *data = ofono_modem_get_data(modem);
+
+	DBG("%p", modem);
+
+	g_at_chat_send(data->aux, "AT+QINISTAT", qinistat_prefix, qinistat_cb,
+			modem, NULL);
+}
+
+static void sim_watch_cb(GAtResult *result, void *user_data)
+{
+	struct ofono_modem *modem = user_data;
+	struct quectel_data *data = ofono_modem_get_data(modem);
+
+	DBG("%p", modem);
+
+	g_at_chat_unregister(data->aux, data->sim_watch);
+	data->sim_watch = 0;
+
+	data->init_timeout = l_timeout_create_ms(500, init_timer_cb, modem, NULL);
+	if (!data->init_timeout) {
+		close_serial(modem);
+		return;
+	}
+}
+
+static enum ofono_sim_state cme_parse(GAtResult *result)
+{
+	struct ofono_error error;
+
+	decode_at_error(&error, g_at_result_final_response(result));
+
+	if (error.type != OFONO_ERROR_TYPE_CME)
+		return OFONO_SIM_STATE_RESETTING;
+
+	switch (error.error) {
+	case 5:
+	case 6:
+	case 7:
+	case 11:
+	case 12:
+	case 17:
+	case 18:
+		return OFONO_SIM_STATE_LOCKED_OUT;
+	case 10:
+		return OFONO_SIM_STATE_NOT_PRESENT;
+	case 13:
+	case 14:
+	case 15:
+		return OFONO_SIM_STATE_RESETTING;
+	default:
+		ofono_error("unknown cpin error: %i", error.error);
+		return OFONO_SIM_STATE_RESETTING;
+	}
+}
+
+static enum ofono_sim_state cpin_parse(GAtResult *result)
+{
+	GAtResultIter iter;
+	const char *cpin;
+
+	g_at_result_iter_init(&iter, result);
+
+	if (!g_at_result_iter_next(&iter, "+CPIN:"))
+		return OFONO_SIM_STATE_RESETTING;
+
+	g_at_result_iter_next_unquoted_string(&iter, &cpin);
+
+	if (g_strcmp0(cpin, "NOT INSERTED") == 0)
+		return OFONO_SIM_STATE_NOT_PRESENT;
+
+	if (g_strcmp0(cpin, "READY") == 0)
+		return OFONO_SIM_STATE_READY;
+
+	return OFONO_SIM_STATE_LOCKED_OUT;
 }
 
 static void cpin_query(gboolean ok, GAtResult *result, gpointer user_data)
 {
-	DBG("%p ok %d", user_data, ok);
+	struct ofono_modem *modem = user_data;
+	struct quectel_data *data = ofono_modem_get_data(modem);
+
+	DBG("%p ok %i", modem, ok);
 
 	if (ok)
-		cpin_notify(result, user_data);
+		data->sim_state = cpin_parse(result);
+	else
+		data->sim_state = cme_parse(result);
+
+	/* Turn off the radio. */
+	g_at_chat_send(data->aux, "AT+CFUN=4", none_prefix, NULL, NULL, NULL);
+
+	switch (data->sim_state) {
+	case OFONO_SIM_STATE_LOCKED_OUT:
+		ofono_modem_set_powered(modem, true);
+		data->sim_watch = g_at_chat_register(data->aux, "+CPIN: READY",
+							sim_watch_cb, FALSE,
+							modem, NULL);
+		if (!data->sim_watch) {
+			ofono_error("failed to create sim watch");
+			close_serial(modem);
+			return;
+		}
+		break;
+	case OFONO_SIM_STATE_READY:
+		data->init_timeout = l_timeout_create_ms(500, init_timer_cb,
+							modem, NULL);
+		if (!data->init_timeout) {
+			ofono_error("failed to create qinitstat timer");
+			close_serial(modem);
+			return;
+		}
+		break;
+	case OFONO_SIM_STATE_RESETTING:
+	case OFONO_SIM_STATE_INSERTED:
+		g_at_chat_send(data->aux, "AT+CPIN?", cpin_prefix, cpin_query,
+				modem, NULL);
+		break;
+	case OFONO_SIM_STATE_NOT_PRESENT:
+		ofono_warn("%s: sim not present", ofono_modem_get_path(modem));
+		ofono_modem_set_powered(modem, true);
+	}
 }
 
 static void cfun_enable(gboolean ok, GAtResult *result, gpointer user_data)
@@ -577,8 +750,8 @@ static void cfun_enable(gboolean ok, GAtResult *result, gpointer user_data)
 		return;
 	}
 
-	data->cpin_ready = g_at_chat_register(data->aux, "+CPIN", cpin_notify,
-						FALSE, modem, NULL);
+	dbus_hw_enable(modem);
+
 	g_at_chat_send(data->aux, "AT+CPIN?", cpin_prefix, cpin_query, modem,
 			NULL);
 }
@@ -659,67 +832,6 @@ static void cgmm_cb(int ok, GAtResult *result, void *user_data)
 			NULL);
 }
 
-static void qinistat_cb(gboolean ok, GAtResult *result, gpointer user_data)
-{
-	struct ofono_modem *modem = user_data;
-	struct quectel_data *data = ofono_modem_get_data(modem);
-	GAtResultIter iter;
-	int status;
-
-	DBG("%p", modem);
-
-	g_at_result_iter_init(&iter, result);
-
-	if (!g_at_result_iter_next(&iter, "+QINISTAT:"))
-		return;
-
-	if (!g_at_result_iter_next_number(&iter, &status))
-		return;
-
-	DBG("qinistat: %d", status);
-
-	if (status != 3) {
-		l_timeout_modify_ms(data->sms_ready_timer, 500);
-		return;
-	}
-
-	ofono_sms_create(modem, data->vendor, "atmodem", data->aux);
-	l_timeout_remove(data->sms_ready_timer);
-	data->sms_ready_timer = NULL;
-}
-
-static void sms_ready_cb(struct l_timeout *timeout, void *user_data)
-{
-	struct ofono_modem *modem = user_data;
-	struct quectel_data *data = ofono_modem_get_data(modem);
-
-	DBG("%p", modem);
-
-	g_at_chat_send(data->aux, "AT+QINISTAT", qinistat_prefix, qinistat_cb,
-			modem, NULL);
-}
-
-static void call_ready_notify(GAtResult *result, void *user_data)
-{
-	struct ofono_modem *modem = user_data;
-	struct quectel_data *data = ofono_modem_get_data(modem);
-
-	DBG("%p", modem);
-
-	g_at_chat_unregister(data->aux, data->call_ready);
-	data->call_ready = 0;
-	data->sms_ready_timer = l_timeout_create_ms(500, sms_ready_cb, modem,
-							NULL);
-	if (!data->sms_ready_timer) {
-		close_serial(modem);
-		return;
-	}
-
-	ofono_phonebook_create(modem, 0, "atmodem", data->aux);
-	ofono_voicecall_create(modem, 0, "atmodem", data->aux);
-	ofono_call_volume_create(modem, 0, "atmodem", data->aux);
-}
-
 static int open_ttys(struct ofono_modem *modem)
 {
 	struct quectel_data *data = ofono_modem_get_data(modem);
@@ -739,20 +851,10 @@ static int open_ttys(struct ofono_modem *modem)
 		return -EIO;
 	}
 
-	data->call_ready = g_at_chat_register(data->aux, "Call Ready",
-						call_ready_notify, false,
-						modem, NULL);
-	if (!data->call_ready) {
-		close_serial(modem);
-		return -ENOTTY;
-	}
-
 	g_at_chat_set_slave(data->modem, data->aux);
 
-	g_at_chat_send(data->modem, "ATE0; &C0; +CMEE=1", none_prefix, NULL,
-			NULL, NULL);
-	g_at_chat_send(data->aux, "ATE0; &C0; +CMEE=1", none_prefix, NULL, NULL,
-			NULL);
+	g_at_chat_send(data->aux, "ATE0; &C0; +CMEE=1; +QIURC=0", none_prefix,
+			NULL, NULL, NULL);
 	g_at_chat_send(data->aux, "AT+CGMM", cgmm_prefix, cgmm_cb, modem,
 			NULL);
 
@@ -1007,6 +1109,8 @@ static int quectel_disable(struct ofono_modem *modem)
 	g_at_chat_send(data->aux, "AT+CFUN=0", cfun_prefix, cfun_disable, modem,
 			NULL);
 
+	data->state = QUECTEL_STATE_INITIALIZING;
+
 	return -EINPROGRESS;
 }
 
@@ -1048,10 +1152,18 @@ static void quectel_pre_sim(struct ofono_modem *modem)
 	DBG("%p", modem);
 
 	ofono_devinfo_create(modem, 0, "atmodem", data->aux);
-	sim = ofono_sim_create(modem, data->vendor, "atmodem", data->aux);
+	data->sim = ofono_sim_create(modem, data->vendor, "atmodem", data->aux);
+	if (!data->sim)
+		return;
 
-	if (sim && data->have_sim == true)
-		ofono_sim_inserted_notify(sim, TRUE);
+	switch (data->sim_state) {
+	case OFONO_SIM_STATE_LOCKED_OUT:
+	case OFONO_SIM_STATE_READY:
+		ofono_sim_inserted_notify(data->sim, true);
+		break;
+	default:
+		break;
+	}
 }
 
 static void quectel_post_sim(struct ofono_modem *modem)
@@ -1068,6 +1180,32 @@ static void quectel_post_sim(struct ofono_modem *modem)
 
 	if (gprs && gc)
 		ofono_gprs_add_context(gprs, gc);
+
+	/*
+	 * the sim related atoms must not be created until the modem is really
+	 * ready, so check the state here
+	 */
+	switch (data->state) {
+	case QUECTEL_STATE_INITIALIZING:
+		/*
+		 * the modem is still initializing, so postpone the atom
+		 * creation until qinistat_cb() determines the modem is
+		 * ready
+		 */
+		data->state = QUECTEL_STATE_POST_SIM;
+		return;
+	case QUECTEL_STATE_READY:
+		/* the modem is ready, so create atoms below */
+		break;
+	default:
+		return;
+	}
+
+	ofono_sms_create(modem, data->vendor, "atmodem", data->aux);
+	ofono_phonebook_create(modem, data->vendor, "atmodem", data->aux);
+	ofono_voicecall_create(modem, data->vendor, "atmodem", data->aux);
+	ofono_call_volume_create(modem, data->vendor, "atmodem", data->aux);
+	data->state = QUECTEL_STATE_INITIALIZED;
 }
 
 static void quectel_post_online(struct ofono_modem *modem)