diff --git a/server/site_tests/firmware_ECUsbPorts/firmware_ECUsbPorts.py b/server/site_tests/firmware_ECUsbPorts/firmware_ECUsbPorts.py
index 8aae527..835a3d0 100644
--- a/server/site_tests/firmware_ECUsbPorts/firmware_ECUsbPorts.py
+++ b/server/site_tests/firmware_ECUsbPorts/firmware_ECUsbPorts.py
@@ -2,6 +2,9 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import logging
+
+from autotest_lib.client.common_lib import error
 from autotest_lib.server.cros.faftsequence import FAFTSequence
 
 
@@ -18,6 +21,9 @@
     # Delay between turning off and on USB ports
     REBOOT_DELAY = 6
 
+    # Timeout range for waiting system to shutdown
+    SHUTDOWN_TIMEOUT = 10
+
 
     def fake_reboot_by_usb_mode_change(self):
         """
@@ -35,12 +41,81 @@
         self.kill_remote()
 
 
+    def get_port_count(self):
+        """
+        Get the number of USB ports by checking the number of GPIO named
+        USB*_ENABLE.
+        """
+        cnt = 0
+        limit = 10
+        while limit > 0:
+            try:
+                gpio_name = "USB%d_ENABLE" % (cnt + 1)
+                self.send_uart_command_get_output(
+                        "gpioget %s" % gpio_name,
+                        "[01].\s*%s" % gpio_name,
+                        timeout=1)
+                cnt = cnt + 1
+                limit = limit - 1
+            except error.TestFail:
+                logging.info("Found %d USB ports" % cnt)
+                return cnt
+
+        # Limit reached. Probably something went wrong.
+        raise error.TestFail("Unexpected error while trying to determine " +
+                             "number of USB ports")
+
+
+    def wait_port_disabled(self, port_count, timeout):
+        """
+        Wait for all USB ports to be disabled.
+
+        Args:
+          port_count: Number of USB ports.
+          timeout: Timeout range.
+        """
+        logging.info('Waiting for %d USB ports to be disabled.' % port_count)
+        while timeout > 0:
+            try:
+                timeout = timeout - 1
+                for idx in xrange(1, port_count+1):
+                    gpio_name = "USB%d_ENABLE" % idx
+                    self.send_uart_command_get_output(
+                            "gpioget %s" % gpio_name,
+                            "0.\s*%s" % gpio_name,
+                            timeout=1)
+                return True
+            except error.TestFail:
+                # USB ports not disabled. Retry.
+                pass
+        return False
+
+
+    def check_power_off_mode(self):
+        """Shutdown the system and check USB ports are disabled."""
+        self._failed = False
+        port_cnt = self.get_port_count()
+        self.faft_client.run_shell_command("shutdown -P now")
+        if not self.wait_port_disabled(port_cnt, self.SHUTDOWN_TIMEOUT):
+            logging.info("Fails to wait for USB port disabled")
+            self._failed = True
+        self.servo.power_short_press()
+
+
+    def check_failure(self):
+        return not self._failed
+
+
     def run_once(self, host=None):
         self.register_faft_sequence((
             {   # Step 1, turn off all USB ports and then turn them on again
                 'reboot_action': self.fake_reboot_by_usb_mode_change,
             },
-            {   # Step 2, dummy step to make sure step 1 reboots
+            {   # Step 2, check USB ports are disabled when powered off
+                'reboot_action': self.check_power_off_mode,
+            },
+            {   # Step 3, check if failure occurred
+                'state_checker': self.check_failure,
             }
         ))
         self.run_faft_sequence()