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1.1.1  Resetting 4100 Latched Faults & Rebooting CPU 
 
When fault  finding the  Simplex®  4100U  Fire Detection  Panel  some  IDNet/MAPNet  &  RUI  faults  will „latch‟ 
and not clear without the use of the „System Reset‟ button (described on a previous page). If all else fails, to 
clear latched faults or some networking issues it may be warranted to use a CPU Reboot otherwise known 
as a Warm-Start.  
 
To  perform  a  Warm-Start,  gain  access  to  the  CPU  card.  The  CPU  card  is  generally  the  only  legacy  card 
(vertically mounted) with its components side facing in a different direction (relative to other cards mounted in 
a similar  fashion)  – otherwise  it  will be  the  only  card  in the panel  with  a  small,  flat and  round  ram battery 
located on it. Once located, find the small push-button switch located on the bottom edge of the card (4100U 
CPU card shown below). Push this button and the panel will then reinitialize. Allow 2-5mins for the panel to 
become fully active and re-establish communications with all its associated devices. 
 
NOTE:  Starting the panel from a powered-down state is referred to as a cold-start.