Discrete Switch And Altitude Inputs - Garmin GNC 420 Maintenance Manual

5.7.6.22 Discrete Switch and Altitude Inputs

For:
1. Apply alternating loads/levels to inputs.
2. Monitor the test results via the Main Discrete Inputs Test Page (Figure 5-11).
3. Verify switching between ACTIVE and INACTIVE loads (listed below) toggles the
corresponding indicator box for each of the input lines listed above.
LOAD < 375 ohms to ground = ACTIVE ________OK
LOAD > 100 K ohms to ground = INACTIVE _______OK
400 SERIES MAINTENANCE MANUAL
P/N 190-00140-05
INPUT NAME
ALTITUDE C4
ALTITUDE C2
ALTITUDE C1
ALTITUDE B4
ALTITUDE B2
ALTITUDE B1
ALTITUDE A4
ALTITUDE A2
ALTITUDE A1
ALTITUDE D4
OBS MODE SELECT
CDI SOURCE SELECT
DEMO MODE SELECT
TEST MODE SELECT
Figure 5-11. Main Discrete Inputs Test Page
PIN
(J1-61)
(J1-62)
(J1-63)
(J1-64)
(J1-65)
(J1-66)
(J1-67)
(J1-68)
(J1-69)
(J1-70)
(J1-71)
(J1-73)
(J1-75)
(J1-76)
Page 5-51
Rev. C