(b)
LRU Tests
1) The LRU tests provide a test armed interrogative message (e.g., 01 FCC TEST?). The test is engaged when the YES/ADV switch is pressed. The selected test first verifies that all prerequisites are available and automatically monitors the interfaces. Any missing prerequisite or interface fault is displayed.
2) Any missing prerequisite or interface fault ends the test. If all prerequisites and interfaces are present, the test executes the appropriate automatic and manual tests. Automatic tests being run are indicated by an IN PROGRESS message. A fault message is indicated for each invalid test. Manual tests provide action messages, verify responses, and display failures. At completion of the test, a TEST COMPLETE message is displayed. The test is exited when the YES/ADV or NO/SKIP switch is pressed.
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Ground Tests Mode
Figure 12
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(c)
System Tests
1) The system tests provide a test armed interrogative message (e.g., 30 CURRENT FAULT REPORT?). The test is engaged when the YES/ADV switch is pressed. The selected test first verifies that all test prerequisites are available. Any missing prerequisite is displayed, and the test ends. The system test automatically arms and engages the appropriate LRU and support tests. A TEST COMPLETE message is displayed after all system tests have been completed and ground faults displayed. The test is exited when the YES/ADV or NO/SKIP switch is pressed.
(d)
Support Tests
1) The support tests provide a test armed interrogative message (e.g., 52 TMC RLY/SW TEST?). The test is engaged when the YES/ADV switch is pressed. The selected test first verifies that all test prerequisites are available. Any missing prerequisite is displayed and the test ends. A TEST COMPLETE message is displayed after completion of all operator interaction tests. The test is exited when the YES/ADV or NO/SKIP switch is pressed.
(12) MCDP Ground Test Mode (Fig. 4)
(a)
The ground test mode assists in isolating recorded flight faults to specific components, and is used to verify system operation after the removal and installation of components. Ground tests require that all the computers and interfacing systems required for a specific test must be installed before the test can be done. Electrical and hydraulic power sources must be supplied to the required components. Ground test mode can be entered anytime after a manual power up, the FAIL annunciator light is turned off, and both AIR/GRD relays indicating on-ground. Two to three operators may be required for certain ground tests interaction.
(b)
Ground Test Entry
1) The ground test mode is entered by pressing the GRD TEST light switch. The closed switch connects a ground that triggers a pulse circuit which generates an interrupt signal to the executive routine (data management). The data management executive routine generates GRD TEST REQ logic that latches GND TEST ENABLE logic when the following conditions are met: Both AIR/GRD relays sense an on-ground condition; MCDP power circuits are operating properly; MCDP is not in automatic-on mode; flight faults are not requested; and ground test is not already engaged. The ground test enabled latch is removed when the flight faults mode is selected; power is removed; or either AIR/GRD relay indicates IN-AIR (relay position does not apply if GRD TEST 51 is enabled).
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