UPS Aviation Technologies Apollo SL70R, Installation Manual

Page: 29 / 52

Troubleshooting
Apollo SL70R Installation Manual
21
4. T
ROUBLESHOOTING
4.1 T
ROUBLESHOOTING
P
ROCEDURE
This appendix provides information to assist troubleshooting if problems occur after
completing the installation. Use Table 4-1 to assist in troubleshooting.
Table 4-1. Troubleshooting Guide
Problem Cause Solution
The SL70R does not power on. The unit is not getting power. Check power connections, breakers,
and main avionics switch.
The altitude is not correct. The unit is not getting the correct
altitude. If the gray code inputs are used,
check all connections from the alti-
tude source and/or verify the altitude
source.
If the host is providing serial altitude
input check for the correct baud rate
and connections.
The unit fails the start-up
self-test. NOTE: System status
message will report failures. TX fails. Check antenna connections. May
have an open, a short, or a bad
VSWR.
Other failure. The unit may need repair. Contact the
factory for assistance.
The unit does not generate re-
plies. The unit is in standby. The unit must be in either the “On” or
“Alt” modes to generate replies.
The unit is not receiving interrogation
signals. Check the antenna connections.
No interrogation signal available. Need to either use a ramp test set or
climb to altitude where ATC radar
service is available.