User's Manual

Table Of Contents
SYSTEM DESCRIPTION AND INSTALLATION MANUAL
T
3
CAS/Part No.9005000
G. Hybrid Surveillance Test / Fault Isolation Procedure
The installer of the T
3
CAS unit with hybrid surveillance (Part No. 9005000-11801 and -
55801) should be aware of the requirement (TSO-C119d and AC 20-151B) to either have
a failure annunciation on the flight deck indicating to the pilot when hybrid surveillance
functionality has failed or perform a scheduled maintenance task to verify that the
function is (and has been) functional. The recommended scheduled maintenance
interval is every 24 months. In addition, a periodic reliability report summarizing all of the
hybrid surveillance faults must be provided to the TCAS manufacturer no later than every
18 months. The following paragraphs describe the recommended procedure for
performing the maintenance check.
Initiate TCAS Short Test. If TCAS Short Test annunciates the fault “Check ADS-B
Inputs”, then hybrid surveillance is failed and troubleshooting will be required. Refer to
the following paragraphs.
If hybrid surveillance is failed, it will be necessary to clear the failure condition and verify
that the fault has been cleared. In order to clear the fault, provide a valid GPS position
solution and a valid True Heading input to the T
3
CAS unit. This may require satellite
visibility and positioning the aircraft outside the hangar. After this is accomplished, verify
the hybrid surveillance fault has been cleared by performing any of the following
methods:
Initiate TCAS Short Test and verify the aural “Check ADS-B Inputs” is not
annunciated.
If a maintenance computer is available, verify the fault
“TCAS_HYBRID_SURV_FAULT” is not reported.
Another method for checking for the hybrid surveillance failure is by monitoring the
TA/RA Display output bus (RMP-7C/7D or RMP-7G/7H) or Maintenance Computer
output bus (RBP-6E/6F), Label 350 (maintenance word), bit 21 (hybrid surveillance
input status). If bit 21 = 1, hybrid surveillance is failed.
If the hybrid surveillance function remains failed after verifying all required hybrid
surveillance inputs (i.e. valid GPS Position and True Heading) have been provided to the
T
3
CAS unit, connect the WebEDDIT tool to the T
3
CAS unit and verify GPS or True
Heading faults are not presently logged. Refer to the note below for instructions on how
to “Dump Active Faults”. If the hybrid surveillance function remains failed after verifying
that GPS or True Heading faults are not presently logged or the tool WebEDDIT is not
available, contact ACSS Customer Services.
NOTE:
If a Windows PC with the ACSS maintenance tool WebEDDIT is available,
connect the tool to the T
3
CAS unit via an RS-232 interface. The RS-232
cable is connected from the Windows PC communications port (UART) to the
T
3
CAS data loader connector. Open WebEDDIT and establish communication
with T
3
CAS, enter the “Common Maintenance Interface” page from the Main
Menu, then enter “Fault Logs and Event Logs” and select “Dump Active
Faults”.
Pub. No. 8600200-001, Revision 004
34-45-29
6-59
04 Nov2014
Use or disclosure of information on this page is subject to the restrictions in the proprietary notice of this document.