400 SERIES INSTALLATION MANUAL Page v
P/N 190-00140-02 Page Rev L
400 SERIES HARDWARE MOD LEVEL HISTORY
The following table identifies hardware modification (Mod) Levels for the GPS 400, GNC 420 and
GNS 430. Mod Levels are listed with the associated service bulletin number, service bulletin date, and
the purpose of the modification. The table is current at the time of publication of this manual (see date on
front cover) and is subject to change without notice. Authorized Garmin Sales and Service Centers are
encouraged to access the most up-to-date bulletin and advisory information on the Garmin Dealer Resource
web site at www.garmin.com using their Garmin -provided user name and password.
MOD
LEVEL
SERVICE
BULLETIN
NUMBER
SERVICE
BULLETIN
DATE
PURPOSE OF MODIFICATION
1 9905 9/17/99 CDI/HSI deviation error; GNS 430, P/N 011-
00280-00, GNC 420, P/N 011-00506-00, GPS
400, P/N 011-00504-00
1 0019 11/07/00 Replace fuse in COM circuit with a resistor;
GNS 430, P/N 011-00280-10, GNC 420, P/N
011-00506-10, GNS 530, P/N 011-00550-10
2 0101 2/16/01 Remote COM transfer
3 0203, Rv B 8/12/02 Improve receiver audio compressor
performance
4 0207 4/2/02 Remove excess solder from COM board
5 0211 6/4/02 Reduce input transients from Audio Panel
Note: Throughout this document references made to GNS 430 and GNC 420 shall equally apply to
the GNS 430A and GNC 420A except where specifically noted.
