8.  Remove  the  DASD  board  assembly. 
9.  Install  the  DASD  board  assembly  by  reversing  the  removal  procedure.  After  exchanging  an  item,  go  to 
“Verify  the  repair”  on  page  558.
This  ends  the  procedure.
Models  830/SB2  -  Device  board  (DB3) 
For  use  by  authorized  service  providers. 
Use  this  procedure  to  remove  or  replace  the  device  board  (DB3)  in  the  Models  830/SB2. 
To  remove  or  replace  the  device  board  (DB3): 
1.  Power  off  the  system.  (See  “Power  on/off  the  system  and  logical  partitions”  on  page  561.) 
2.  Disconnect  the  power  cord  from  the  system  unit. 
3.  Open  the  rear  cover.  (See  “Models  830/SB2  with  FC  9074  -  Covers”  on  page  58.) 
4.  Refer  to  Final  assembly,  front  -  Models  830  and  SB2  with  FC  9074  (See  page  400)  and  perform  the 
following  steps. 
5.  From  the  rear  of  the  unit  do  the  following: 
a.  Remove  the  EMC  access  plate  that  is  located  directly  above  the  PCI  card  enclosure.  Press  the 
surfaces  of  the  two  latching  mechanisms  together  and  tilt  the  top  of  the  cover  away  from  the  frame 
to  remove  it. 
b.  Remove  the  cables  from  the  disk  unit  controller  cards  (IOAs)  that  are  located  inside  the  PCI  card 
enclosure  and  note  their  locations. 
Note:  Both  ends  of  the  ribbon  cables  are  marked  LH  or  RH  indicating  that  one  end  of  the  cable  is 
plugged  in  to  either  the  left-hand  (DB1)  or  right-hand  (DB2)  DASD  board  assembly.  The  other  end 
of  the  cable  is  plugged  in  to  either  the  left-most  (LH)  or  right-most  (RH)  DASD  controller  card.  The 
cables  will  crisscross  in  the  center  of  the  tower. 
c.  Remove  the  screws  that  hold  the  PCI  card  enclosure  in  the  frame. 
d.  Pull  the  PCI  card  enclosure  partially  out  of  the  frame  while  lifting  the  cables  clear  of  the  enclosure. 
e.  Press  the  release  mechanism  that  is  located  along  the  top  right  side  of  the  enclosure  and  carefully 
slide  the  enclosure  towards  you.  Make  sure  that  the  cables  are  clear  of  the  enclosure. 
f.  Remove  the  PCI  card  enclosure  from  the  frame. 
g.  Remove  the  screws  from  the  EMC  access  plate  that  is  located  inside  the  frame  and  directly  above 
the  power  distribution  board. 
h.  Remove  the  EMC  access  plate. 
i.  Reach  through  the  opening  and  remove  the  cables  from  the  backside  of  the  base  DASD  board 
assembly  (DB3).
6.
  Open  the  front  cover.  (See  “Models  840/SB3  -  Covers”  on  page  80.) 
7.  From  the  front  of  the  system  do  the  following: 
a.  Note  the  removable  media  locations  and  then  remove  them  by  pulling  out  on  the  handles  which  are 
located  on  each  side  of  the  unit. 
b.  Remove  the  operator  panel  by  pulling  on  the  handles  that  are  located  on  each  side  of  the  unit  and 
sliding  it  partially  out  of  the  tower.  Then,  unplug  the  cable  from  the  rear  of  the  control  panel.  (See 
Final  assembly,  front  -  Models  830  and  SB2  with  FC  9074  (See  page  396).) 
c.  Unplug  the  control  panel  cable  from  the  base  DASD  board  assembly  (DB3). 
d.  Remove  the  two  retaining  screws  that  are  located  inside  of  the  removable  media  enclosure  (the  top 
right  and  lower  left  corners). 
e.  Remove  the  removable  media  enclosure. 
f.  Remove  the  EMC  access  plates  from  the  disk  unit  enclosures  that  are  located  in  front  of  the 
backplane  (DB3).  For  location  information,  see  “Locations  —  Models  830,  SB2  System  Unit  with  FC 
 
Analyze  hardware  problems  61