Power  system  checkout 
To  verify  a  symptom,  do  the  following: 
1.  Power  off  the  computer. 
2.  Remove  the  battery  pack. 
3.  Connect  the  ac  adapter. 
4.  Check  that  power  is  supplied  when  you  power  on  the 
computer. 
5.  Power  off  the  computer. 
6.  Disconnect  the  ac  adapter  and  install  the  charged 
battery  pack. 
7.  Check  that  the  battery  pack  supplies  power  when  you 
power  on  the  computer.
If
  you  suspect  a  power  problem,  see  the  appropriate  one 
of  the  following  power  supply  checkouts: 
v  “Checking  the  ac  adapter” 
v  “Checking  operational  charging”  on  page  47 
v  “Checking  the  battery  pack”  on  page  47 
v  “Checking  the  backup  battery”  on  page  48
Checking  the  ac  adapter 
You  are  here  because  the  computer  fails  only  when  the  ac 
adapter  is  used: 
v  If  the  power  problem  occurs  only  when  the  port 
replicator  is  used,  replace  the  port  replicator. 
v  If  the  power-on  indicator  does  not  turn  on,  check  the 
power  cord  of  the  ac  adapter  for  correct  continuity  and 
installation. 
v  If  the  computer  does  not  charge  during  operation,  go  to 
″Checking  operational  charging.″ 
To  check  the  ac  adapter,  do  the  following: 
1.  Unplug  the  ac  adapter  cable  from  the  computer. 
2.  Measure  the  output  voltage  at  the  plug  of  the  ac 
adapter  cable.  See  the  following  figure: 
 
2
1
(16 - 10 V)
 
 
Pin  Voltage  (V  dc) 
1  +15.5  to  +17.0 
2  Ground 
 
3.  If  the  voltage  is  not  correct,  replace  the  ac  adapter. 
4.  If  the  voltage  is  acceptable,  do  the  following: 
v  Replace  the  system  board. 
v  If  the  problem  persists,  go  to  “Product  overview”  on 
page  51.
Note:  Noise  from  the  ac  adapter  does  not  always  indicate 
a  defect.
Checkout  guide  
46  MT  2369/2370/2371/2372/2382/2386