(1) Make sure DME 1 and DME 2 are not tuned to a local station’s frequency.
(2) Push and hold the TEST button on the captain’s navigation control panel to start the DME 1 self test.
(a) Make sure the DME 2 shows dashes on the displays during the DME 1 self test.
(b) Make sure the DME 1 has a flag on the displays for approximately two seconds.
(c) Make sure the DME 1 shows dashes on the displays until the end of the test.
(3) Release the TEST button on the captain’s navigation control panel.