Honeywell SPZ-8000 Pilot's Manual page 273

If a failure is detected during TEST mode, a corresponding fault code
is generated. Fault codes are displayed as part of the FAIL annunciator
i.e., FAIL "N", where "N" is the fault code. (Refer to Table C--3.)
NOTES: 1. Some weather failures are annunciated on the
2. Some EFIS/MFD installations power up with
EFIS Fault Code
00
01
02
03
04
05
06
07
A28--1146--055
REV 2
SPZ--8000 Digital Integrated Flight Control System
EFIS/MFD with WX.
displayed if the weather radar is turned off.
No fault detected.
The antenna is not scanning or it is not
scanning correctly.
Antenna stabilization errors.
Radar receiver fault.
The radar signal mixer current is out of
specification -- probably due to defective
mixer diodes.
Radar automatic frequency control fault.
Can be caused by defective transmitter.
This fault can be observed in TEST by the
display of a broken noise band.
Indicates abnormal fan current for an
extended period of time.
Central processing unit microprocessor
fault in RTA.
EFIS Fault Code Descriptions
Table C--3
Fault Description
R
PRIMUS
WX
870 Weather Radar
C--15