diff --git a/src/wimax/nm-device-wimax.c b/src/wimax/nm-device-wimax.c
index b30f94725a..9564db3e80 100644
--- a/src/wimax/nm-device-wimax.c
+++ b/src/wimax/nm-device-wimax.c
@@ -1075,7 +1075,7 @@ wmx_scan_result_cb (struct wmxsdk *wmxsdk,
 		if (net_type != nm_wimax_nsp_get_network_type (nsp))
 			g_object_set (nsp, NM_WIMAX_NSP_NETWORK_TYPE, net_type, NULL);
 
-		signalq = sdk_nsp->linkQuality;
+		signalq = CLAMP (sdk_nsp->linkQuality, 0, 100);
 		if (signalq != nm_wimax_nsp_get_signal_quality (nsp))
 			g_object_set (nsp, NM_WIMAX_NSP_SIGNAL_QUALITY, signalq, NULL);
 
diff --git a/src/wimax/nm-wimax-nsp.c b/src/wimax/nm-wimax-nsp.c
index e1c9bb885a..b10cee3990 100644
--- a/src/wimax/nm-wimax-nsp.c
+++ b/src/wimax/nm-wimax-nsp.c
@@ -146,7 +146,7 @@ set_property (GObject *object, guint prop_id,
 	case PROP_SIGNAL_QUALITY:
 		quality = g_value_get_uint (value);
 		if (quality != priv->signal_quality) {
-			priv->signal_quality = quality;
+			priv->signal_quality = CLAMP (quality, 0, 100);
 			g_object_notify (object, NM_WIMAX_NSP_SIGNAL_QUALITY);
 		}
 		break;