Displayed Messages:

1. Link Failure - Lack of connection between processor and display
   1. Battery Low - Indicates low battery in display or processor
   2. Stars in place of altitude information when the altitude data is invalid. (This can be momentary, but it indicates a problem even if the starts go away sometimes.)
   3. W - Means a general TCAD failure (normal in part of the test mode.) The self test can be used to get more information.
2. Audible Failure Announcements

•       Code 1 - Means Coupler Failure (usually followed by interrogator failure.)
•       Code 2 - Means suppression shorted.
•       Code 3 - Means receiver failure.
•       Code 4 - Means suppression continuity failure.
•       Altitude Data Invalid - Means the BX is receiving invalid altitude data from the encoder.
•       Gear Down - Issued when the landing gear down input (J1-11) is grounded and the weight on wheels pin (J1-      14) is not grounded (time delay of several minutes before this activates).
•       Ground Mode - Issued when the unit initializes in Ground Mode.
•       Interrogator Failure - Failure of the interrogator portion of the 9900BX.

The messages that may be seen during self-test of the 1/2-3ATI display are "

1.  SYS CHK: FAULT or SYS CHK: OK - The system has found a fault, or it is ok.

2. CW RF DETECTED - This message should not appear, as it is presently unused in the processor, and the processors no longer detect this condition.  The display is still capable of displaying this message if it receives the error from the processor.

3.  COUPLER GROUNDED - Means a short has been detected in the coupler wiring

4.  XMT CHK: FAULT or XMT CHK: OK - Transmitter fault, or Transmitter is OK

5.  BATTERY LOW - If the message is accompanied by **** in the right hand window, the battery fault is referring to the battery in the processor.  If the message IS NOT accompanied by **** the fault is referring to the battery in the display itself.