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Does Your Primus II Transponder Erroneously Go Into Standby?

June 2010

Ever have your Primus II Communication unit (RCZ) transponder erroneously going into standby mode? It often occurs if the flight crew takes longer than five seconds when using the rotary knob of the radio management unit to change the ATC code. Honeywell has issued an Airworthiness Directive that addresses this issue.

AD 2006-19-04 was issued to prevent the transponder of the COM unit from going into standby mode, which could increase the workload on the flight crew and result in improper functioning of the traffic alert and collision avoidance system.

AD 2006-19-04 Part Conversion
From To
7510700-725 7510700-724
-763 -761
-765 -764
-813 -814
-815 -816
-825 -824
-863 -873
-875 -876

The AD is a simple process that requires new software for the XS-85X transponder module and installation of new Product, ID and Mod plates to the RCZ COM unit for future quick reference that the AD has been complied with.

Best of all, if this is the only work required for your unit, the AD is covered under Honeywell warranty. For more information about the Honeywell warranty, contact a Components Solutions Tech Rep.