diff --git a/sys/dev/mii/e1000phy.c b/sys/dev/mii/e1000phy.c
--- a/sys/dev/mii/e1000phy.c
+++ b/sys/dev/mii/e1000phy.c
@@ -185,6 +185,11 @@
 {
 	uint16_t reg, page;
 
+	/* Undo power-down / isolate */
+	reg = PHY_READ(sc, E1000_CR);
+	reg &= ~(E1000_CR_ISOLATE | E1000_CR_POWER_DOWN);
+	PHY_WRITE(sc, E1000_CR, reg);
+
 	reg = PHY_READ(sc, E1000_SCR);
 	if ((sc->mii_flags & MIIF_HAVEFIBER) != 0) {
 		reg &= ~E1000_SCR_AUTO_X_MODE;
@@ -353,6 +358,8 @@
 
 		reg = PHY_READ(sc, E1000_CR);
 		reg &= ~E1000_CR_AUTO_NEG_ENABLE;
+		/* Undo power-down / isolate */
+		reg &= ~(E1000_CR_ISOLATE | E1000_CR_POWER_DOWN);
 		PHY_WRITE(sc, E1000_CR, reg | E1000_CR_RESET);
 
 		if (IFM_SUBTYPE(ife->ifm_media) == IFM_1000_T) {