#12766 HIGH Opportu: XO-1.75 not charging batteries

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#12766: XO-1.75 not charging batteries
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 Reporter:  Quozl                |                 Owner:  Quozl                   
     Type:  task                 |                Status:  new                     
 Priority:  high                 |             Milestone:  Opportunity             
Component:  embedded controller  |               Version:  Software Build 13.2.0-13
 Keywords:                       |           Next_action:  diagnose                
 Verified:  0                    |   Deployment_affected:  ni                      
Blockedby:                       |              Blocking:                          
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 Reproducer:
  * connect power cable, boot to ok, ''watch-battery'',
  * insert battery,

 Expected result:
  * discharging status clear,
  * charging status set,
  * orange battery indicator,
  * charge current of at least 1A,
  * increase of state of charge value,
  * eventual charge completion.

 Observed result:
  * discharging status clear,
  * sometimes charging status set,
  * very low charge current, between 10mA and 90mA if battery at 5.70V,
 about zero if battery at 6.56V,
  * no increase, or very slow increase of state of charge value, 3%
 overnight,

 Other information:
  * isolated to specific set of 25 XO-1.75,
  * batteries work fine in other laptops,
  * battery voltage shows normal increase when load is removed at the point
 that the discharging status is cleared,
  * battery temperature gradient changes when load is removed,
  * the power adapters have not been identified,
  * XO-1.75 1C2 800 MHz, 1GB, 4GB, SHC213000AB, Q4D34, 1.0.01,
  * EC serial log http://dev.laptop.org/~quozl/z/1WSL9Q.txt (laptop turned
 off, two minutes without power cable, two minutes with power cable).

 Action plan:
  * identify the power adapters,
  * measure the DC voltage at the end of the cable,
  * verify orange battery LED status,
  * test the MPPT input voltage measurement using ''.mppt''.

 A field support task, to determine causes.

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Ticket URL: <http://dev.laptop.org/ticket/12766>
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