Garmin GNC 420 Maintenance Manual page 37

Table 3-6. Testing Failures Main Board (continued)
TEST FAILURE
GPS Antenna Bias
GPS Noise
Satellite Tracking Test
Main Lateral Left, Right Outputs
Main Vertical Up, Down Outputs
Main To/From Output
Main Lateral Flag Output
Main Vertical Flag Output
Main Lateral Super Flag Output
Main Vertical Super Flag Output
Annunciate Outputs
OBI Serial Interface
Discrete Switch and Altitude Inputs
ARINC 429 Xmit and Rcvr
429 RX 1 and 2 Low Speed
429 RX 1 and 2 High Speed
GPS RS232 1
GPS RS232 2
GPS RS232 3
GPS RS232 4
OBS
400 SERIES MAINTENANCE MANUAL
P/N 190-00140-05
TEST
PARAGRAPH
5.7.6.10 Replace GPS Module (see paragraph 4.5.5)
5.7.6.11 Replace GPS Module (see paragraph 4.5.5)
Replace Main Board (see paragraph 4.5.5)
5.7.6.12 Replace GPS Module (see paragraph 4.5.5)
Replace Main Board (see paragraph 4.5.5)
5.7.6.13 Replace Main Board (see paragraph 4.5.5)
5.7.6.14 Replace Main Board (see paragraph 4.5.5)
5.7.6.15 Replace Main Board (see paragraph 4.5.5)
5.7.6.16 Replace Main Board (see paragraph 4.5.5)
5.7.6.17 Replace Main Board (see paragraph 4.5.5)
5.7.6.18 Replace Main Board (see paragraph 4.5.5)
5.7.6.19 Replace Main Board (see paragraph 4.5.5)
5.7.6.20 Replace Main Board (see paragraph 4.5.5)
5.7.6.21 Replace Main Board (see paragraph 4.5.5)
5.7.6.22
5.7.6.23 Replace Main Board (see paragraph 4.5.5)
5.7.6.23A Replace Main Board (see paragraph 4.5.5)
5.7.6.23A Replace Main Board (see paragraph 4.5.5)
5.7.6.24A Replace Main Board (see paragraph 4.5.5)
5.7.6.24B Replace Main Board (see paragraph 4.5.5)
5.7.6.24C Replace Main Board (see paragraph 4.5.5)
5.7.6.24D Replace Main Board (see paragraph 4.5.5)
5.7.6.25 Replace Main Board (see paragraph 4.5.5)
RECOMMENDED ACTION
Page 3-11
Rev. C