diff --git a/sys/dev/aq/aq_fw2x.c b/sys/dev/aq/aq_fw2x.c
--- a/sys/dev/aq/aq_fw2x.c
+++ b/sys/dev/aq/aq_fw2x.c
@@ -657,6 +657,9 @@
 	uint16_t ctrl;
 	int err;
 
+	if ((hw->fw_caps & FW2X_CAP_TEMPERATURE) == 0)
+		return (ENOTSUP);
+
 	mtx_lock(&hw->fw_mtx);
 	aq_fw2x_phy_id_probe(hw);
 	err = aq_fw2x_phy_read(hw, AQ_PHY_MMD_GLOBAL, AQ_PHY_THERMAL_CTRL_REG,
diff --git a/sys/dev/aq/aq_main.c b/sys/dev/aq/aq_main.c
--- a/sys/dev/aq/aq_main.c
+++ b/sys/dev/aq/aq_main.c
@@ -782,10 +782,12 @@
 	softc->init_retries = 0;
 
 	/* aq_hw_init reloads the PHY, resetting the thermal-shutdown arming. */
-	if (hw->fw_ops->thermal_arm != NULL &&
-	    hw->fw_ops->thermal_arm(hw) != 0)
-		device_printf(softc->dev,
-		    "could not arm PHY thermal shutdown\n");
+	if (hw->fw_ops->thermal_arm != NULL) {
+		err = hw->fw_ops->thermal_arm(hw);
+		if (err != 0 && err != ENOTSUP)
+			device_printf(softc->dev,
+			    "could not arm PHY thermal shutdown\n");
+	}
 
 	aq_if_media_status(ctx, &ifmr);