Troubleshooting and Maintenance 
Troubleshooting Your Computer 
168  Corporate Evaluator’s Guide 
If a secondary battery doesn’t charge 
•  The computer’s secondary battery won’t charge until the main battery is fully 
charged. 
•  Make sure the AC adapter is fully plugged into the power source and the computer, 
and that the light on the adapter is on. 
•  Make sure the secondary battery is correctly installed and locked in place. 
If the computer has a short operating time 
•  Try conserving power using any of the suggestions listed in “To get the most from 
your batteries” on page 55. 
•  If you are running an application that has an automatic save feature (such as 
MS Word), disable this feature or increase the specified save time to reduce hard disk 
access. 
•  If the operating time has gradually become shorter and the battery is more than a year 
or two old, you may need to replace the battery. 
•  Heavy modem use can affect battery operating time. 
•  PC card use can affect battery operating time. 
•  The battery gauge may need to be calibrated. Restart the computer, press F6 when the 
HP logo appears, and follow the instructions that appear onscreen. The process 
calibrates the main battery and any secondary batteries in the module bay, and 
requires four to five hours per battery. You cannot use the computer during this 
process. 
If the Time Remaining for the battery is not correct 
•  The Time Remaining is an estimate, not a precise value, and is based on the rate at 
which the computer is using power at the moment. This value therefore depends on 
your current task, and assumes that you will continue using power at the same rate 
until the battery runs out. So, if you check the Time Remaining while the computer is 
performing a task requiring a good deal of power (such as reading from a CD or 
DVD), the value will probably show less time remaining than you really have, since 
you will probably later switch to tasks that require less power.