Safety  inspection  guide 
The  purpose  of  this  inspection  guide  is  to  assist  you  in 
identifying  potentially  unsafe  conditions.  As  each  machine 
was  designed  and  built,  required  safety  items  were 
installed  to  protect  users  and  service  personnel  from  injury. 
This  guide  addresses  only  those  items.  You  should  use 
good  judgment  to  identify  potential  safety  hazards  due  to 
attachment  of  non-ThinkPad  features  or  options  not 
covered  by  this  inspection  guide. 
If  any  unsafe  conditions  are  present,  you  must  determine 
how  serious  the  apparent  hazard  could  be  and  whether 
you  can  continue  without  first  correcting  the  problem. 
Consider  these  conditions  and  the  safety  hazards  they 
present: 
v  Electrical  hazards,  especially  primary  power  (primary 
voltage  on  the  frame  can  cause  serious  or  fatal 
electrical  shock) 
v  Explosive  hazards,  such  as  a  damaged  CRT  face  or  a 
bulging  capacitor 
v  Mechanical  hazards,  such  as  loose  or  missing  hardware
To
  determine  whether  there  are  any  potentially  unsafe 
conditions,  use  the  following  checklist  at  the  beginning  of 
every  service  task.  Begin  the  checks  with  the  power  off, 
and  the  power  cord  disconnected. 
Checklist: 
1.  Check  exterior  covers  for  damage  (loose,  broken,  or 
sharp  edges). 
2.  Power  off  the  computer.  Disconnect  the  power  cord. 
3.  Check  the  power  cord  for: 
a.  A  third-wire  ground  connector  in  good  condition. 
Use  a  meter  to  measure  third-wire  ground 
continuity  for  0.1  ohm  or  less  between  the  external 
ground  pin  and  the  frame  ground. 
b.  The  power  cord  should  be  the  type  specified  in  the 
parts  list. 
c.  Insulation  must  not  be  frayed  or  worn.
4.
  Remove  the  cover. 
5.  Check  for  any  obvious  non-ThinkPad  alterations.  Use 
good  judgment  as  to  the  safety  of  any  non-ThinkPad 
alterations. 
6.  Check  inside  the  unit  for  any  obvious  unsafe 
conditions,  such  as  metal  filings,  contamination,  water 
or  other  liquids,  or  signs  of  fire  or  smoke  damage. 
7.  Check  for  worn,  frayed,  or  pinched  cables. 
Safety  information 
Introduction  19