diff --git a/locale/circuitpython.pot b/locale/circuitpython.pot
index 1c92d3765f..434684e137 100644
--- a/locale/circuitpython.pot
+++ b/locale/circuitpython.pot
@@ -2013,7 +2013,8 @@ msgid "Unhandled ESP TLS error %d %d %x %d"
 msgstr ""
 
 #: shared-bindings/wifi/Radio.c
-msgid "Unknown failure"
+#, c-format
+msgid "Unknown failure %d"
 msgstr ""
 
 #: ports/nrf/common-hal/_bleio/__init__.c
diff --git a/ports/esp32s2/common-hal/wifi/Radio.c b/ports/esp32s2/common-hal/wifi/Radio.c
index e9f374a06b..9302300889 100644
--- a/ports/esp32s2/common-hal/wifi/Radio.c
+++ b/ports/esp32s2/common-hal/wifi/Radio.c
@@ -168,11 +168,11 @@ wifi_radio_error_t common_hal_wifi_radio_connect(wifi_radio_obj_t *self, uint8_t
     } while ((bits & (WIFI_CONNECTED_BIT | WIFI_DISCONNECTED_BIT)) == 0 && !mp_hal_is_interrupted());
     if ((bits & WIFI_DISCONNECTED_BIT) != 0) {
         if (self->last_disconnect_reason == WIFI_REASON_AUTH_FAIL) {
-            return WIFI_RADIO_ERROR_AUTH;
+            return WIFI_RADIO_ERROR_AUTH_FAIL;
         } else if (self->last_disconnect_reason == WIFI_REASON_NO_AP_FOUND) {
             return WIFI_RADIO_ERROR_NO_AP_FOUND;
         }
-        return WIFI_RADIO_ERROR_UNKNOWN;
+        return self->last_disconnect_reason;
     }
     return WIFI_RADIO_ERROR_NONE;
 }
diff --git a/ports/esp32s2/common-hal/wifi/__init__.c b/ports/esp32s2/common-hal/wifi/__init__.c
index 08d7a164f4..b8e8f731bd 100644
--- a/ports/esp32s2/common-hal/wifi/__init__.c
+++ b/ports/esp32s2/common-hal/wifi/__init__.c
@@ -65,11 +65,9 @@ static void event_handler(void* arg, esp_event_base_t event_base,
                 uint8_t reason = d->reason;
                 ESP_LOGW(TAG, "reason %d 0x%02x", reason, reason);
                 if (radio->retries_left > 0 &&
-                        (reason == WIFI_REASON_AUTH_EXPIRE ||
-                         reason == WIFI_REASON_NOT_AUTHED ||
-                         reason == WIFI_REASON_ASSOC_EXPIRE ||
-                         reason == WIFI_REASON_CONNECTION_FAIL ||
-                         reason == WIFI_REASON_4WAY_HANDSHAKE_TIMEOUT)) {
+                        reason != WIFI_REASON_AUTH_FAIL &&
+                        reason != WIFI_REASON_NO_AP_FOUND &&
+                        reason != WIFI_REASON_ASSOC_LEAVE) {
                     radio->retries_left--;
                     ESP_LOGI(TAG, "Retrying connect. %d retries remaining", radio->retries_left);
                     esp_wifi_connect();
diff --git a/shared-bindings/wifi/Radio.c b/shared-bindings/wifi/Radio.c
index 63f507067a..8181fc4c96 100644
--- a/shared-bindings/wifi/Radio.c
+++ b/shared-bindings/wifi/Radio.c
@@ -218,12 +218,12 @@ STATIC mp_obj_t wifi_radio_connect(size_t n_args, const mp_obj_t *pos_args, mp_m
     }
 
     wifi_radio_error_t error = common_hal_wifi_radio_connect(self, ssid.buf, ssid.len, password.buf, password.len, args[ARG_channel].u_int, timeout, bssid.buf, bssid.len);
-    if (error == WIFI_RADIO_ERROR_AUTH) {
+    if (error == WIFI_RADIO_ERROR_AUTH_FAIL) {
         mp_raise_ConnectionError(translate("Authentication failure"));
     } else if (error == WIFI_RADIO_ERROR_NO_AP_FOUND) {
         mp_raise_ConnectionError(translate("No network with that ssid"));
     } else if (error != WIFI_RADIO_ERROR_NONE) {
-        mp_raise_ConnectionError(translate("Unknown failure"));
+        mp_raise_msg_varg(&mp_type_ConnectionError, translate("Unknown failure %d"), error);
     }
 
     return mp_const_none;
diff --git a/shared-bindings/wifi/Radio.h b/shared-bindings/wifi/Radio.h
index 1e8f362e34..64c1052f7b 100644
--- a/shared-bindings/wifi/Radio.h
+++ b/shared-bindings/wifi/Radio.h
@@ -36,10 +36,39 @@
 const mp_obj_type_t wifi_radio_type;
 
 typedef enum {
-    WIFI_RADIO_ERROR_NONE,
-    WIFI_RADIO_ERROR_UNKNOWN,
-    WIFI_RADIO_ERROR_AUTH,
-    WIFI_RADIO_ERROR_NO_AP_FOUND
+    // 0 is circuitpython-specific; 1-53 are IEEE; 200+ are Espressif
+    WIFI_RADIO_ERROR_NONE                     = 0,
+    WIFI_RADIO_ERROR_UNSPECIFIED              = 1,
+    WIFI_RADIO_ERROR_AUTH_EXPIRE              = 2,
+    WIFI_RADIO_ERROR_AUTH_LEAVE               = 3,
+    WIFI_RADIO_ERROR_ASSOC_EXPIRE             = 4,
+    WIFI_RADIO_ERROR_ASSOC_TOOMANY            = 5,
+    WIFI_RADIO_ERROR_NOT_AUTHED               = 6,
+    WIFI_RADIO_ERROR_NOT_ASSOCED              = 7,
+    WIFI_RADIO_ERROR_ASSOC_LEAVE              = 8,
+    WIFI_RADIO_ERROR_ASSOC_NOT_AUTHED         = 9,
+    WIFI_RADIO_ERROR_DISASSOC_PWRCAP_BAD      = 10,
+    WIFI_RADIO_ERROR_DISASSOC_SUPCHAN_BAD     = 11,
+    WIFI_RADIO_ERROR_IE_INVALID               = 13,
+    WIFI_RADIO_ERROR_MIC_FAILURE              = 14,
+    WIFI_RADIO_ERROR_4WAY_HANDSHAKE_TIMEOUT   = 15,
+    WIFI_RADIO_ERROR_GROUP_KEY_UPDATE_TIMEOUT = 16,
+    WIFI_RADIO_ERROR_IE_IN_4WAY_DIFFERS       = 17,
+    WIFI_RADIO_ERROR_GROUP_CIPHER_INVALID     = 18,
+    WIFI_RADIO_ERROR_PAIRWISE_CIPHER_INVALID  = 19,
+    WIFI_RADIO_ERROR_AKMP_INVALID             = 20,
+    WIFI_RADIO_ERROR_UNSUPP_RSN_IE_VERSION    = 21,
+    WIFI_RADIO_ERROR_INVALID_RSN_IE_CAP       = 22,
+    WIFI_RADIO_ERROR_802_1X_AUTH_FAILED       = 23,
+    WIFI_RADIO_ERROR_CIPHER_SUITE_REJECTED    = 24,
+    WIFI_RADIO_ERROR_INVALID_PMKID            = 53,
+    WIFI_RADIO_ERROR_BEACON_TIMEOUT           = 200,
+    WIFI_RADIO_ERROR_NO_AP_FOUND              = 201,
+    WIFI_RADIO_ERROR_AUTH_FAIL                = 202,
+    WIFI_RADIO_ERROR_ASSOC_FAIL               = 203,
+    WIFI_RADIO_ERROR_HANDSHAKE_TIMEOUT        = 204,
+    WIFI_RADIO_ERROR_CONNECTION_FAIL          = 205,
+    WIFI_RADIO_ERROR_AP_TSF_RESET             = 206,
 } wifi_radio_error_t;
 
 extern bool common_hal_wifi_radio_get_enabled(wifi_radio_obj_t *self);