Universal  Serial  Bus  (USB)  port  problems 
 
v  Follow  the  suggested  actions  in  the  order  in  which  they  are  listed  in  the  Action  column  until  the  problem 
is  solved. 
v  See  the  parts  listing  in  the  Problem  Determination  and  Service  Guide  to  determine  which  components  are 
customer  replaceable  units  (CRU)  and  which  components  are  field  replaceable  units  (FRU). 
v  If  an  action  step  is  preceded  by  “(Trained  service  technician  only),”  that  step  must  be  performed  only  by  a 
trained  service  technician. 
Symptom  Action 
A  USB  device  does  not  work. 
1.  Make  sure  that: 
v  The  correct  USB  device  driver  is  installed. 
v  The  operating  system  supports  USB  devices.
2.
  Make  sure  that  the  USB  configuration  options  are  set  correctly  in  the 
Configuration/Setup  Utility  program  menu  (see  the  User’s  Guide  for  more 
information). 
3.  If  you  are  using  a  USB  hub,  disconnect  the  USB  device  from  the  hub  and 
connect  it  directly  to  the  server. 
4.  Move  the  device  cable  to  a  different  USB  connector.
 
Video  problems 
See  “Monitor  problems”  on  page  68. 
Light  path  diagnostics 
Use  light  path  diagnostics  to  diagnose  system  errors.  The  light  path  diagnostics 
panel  is  behind  the  operator  information  panel,  on  the  left  front  of  the  server.  To 
access  the  light  path  diagnostics  panel,  slide  the  release  latch  on  the  front  of  the 
operator  information  panel  to  the  left. 
The  following  illustration  shows  the  controls  and  LEDs  on  the  light  path  diagnostics 
panel. 
DASD
NMI
PCI
PS1
SP
PS2
CNFG
MEM
CPU
FAN
VRM
OVER SPEC
TEMP
REMIND
S ERR
Light Path
Diagnostics
RAID
BRD
 
 
To  acknowledge  a  system  error  but  not  take  immediate  action,  press  the  remind 
button  to  place  the  server  in  Remind  mode.  When  the  server  is  in  Remind  mode, 
the  system-error  LED  on  the  front  of  the  server  flashes.  If  a  new  failure  occurs,  the 
system-error  LED  is  lit  again. 
 
74  IBM  System  x3650  Type  7979:  Installation  Guide