67 Chapter 4Check the Battery PackTo check the battery pack, do the following:From Software:1. Check out the Power Management in control Panel2. In Power Meter, confirm that if the parameters shown in the screen for Current Power Source and TotalBattery Power Remaining are correct.3. Repeat the steps 1 and 2, for both battery and adapter.4. This helps you identify first the problem is on recharging or discharging.From Hardware:1. Power off the computer.2. Remove the battery pack and measure the voltage between battery terminals 1(+) and 6(ground). See thefollowing figure3. If the voltage is still less than 7.5 Vdc after recharging, replace the battery.To check the battery charge operation, use a discharged battery pack or a battery pack that has less than 50%of the total power remaining when installed in the computer.If the battery status indicator does not light up, remove the battery pack and let it return to room temperature.Re-install the battery pack.If the charge indicator still does not light up, replace the battery pack. If the charge indicator still does not lightup, replace the DC/DC charger board.Touchpad CheckIf the touchpad doesn’t work, do the following actions one at a time to correct the problem. Do not replace anon-defective FRU:1. After rebooting, run Tracking Pad PS2 Mode Driver. For example, run Syn touch driver.2. Run utility with the PS/2 mouse function and check if the mouse is working.3. If the PS/2 mouse does not work, then check if the main board to switch board FPC is connected O.K.4. If the main board to switch board FPC is connected well, then check if the FCC on touch pad PCBconnects properly.5. If the FFC on touch pad PCB connects properly, then check if LS851 JP1 Pin6=5V are pulsed. If yes, thenreplace switch board. If no, then go to next step.6. Replace touch pad PCB.7. If the touch pad still does not work, then replace FPC on Track Pad PCB.After you use the touchpad, the pointer drifts on the screen for a short time. This self-acting pointer movementcan occur when a slight, steady pressure is applied to the touchpad pointer. This symptom is not a hardwareproblem. No service actions are necessary if the pointer movement stops in a short period of time.Display Check1. Connect an external display to the computer’s external monitor port, the boot the computer. The computercan automatically detect the external display. Press Fn+ p to switch to the external display.2. If the external display works fine, the internal LCD may be damaged. Then perform the following steps:Make sure the DDRRAM module is seated properly. Then run the diplay test again. If the problemstill exists, go to next step.Replace the inverter board, then run the display test program again. If the problem still occurs, goon next step.Replace the LCD module with a new one then run the display test again. If the probelm stillhappens, continue next step.