If ThinkPad battery drains very low or completely, system might not boot up or BitLocker PIN problems might occur.
The problems might occur when the ThinkPad system is powered on after the system battery has drained completely.
Here is a list of symptoms that might be encountered:
- LEDs flash, but system does not power up (Lenovo Logo screen does not display).
- System powers on but stops with 1-3-3-1 beep sequence.
- System boots up in Windows Vista with BitLocker activated, but BitLocker does not accept the BitLocker PIN (48-character password is required).
Any of the following ThinkPad systems running any Operating System with battery drains very low or completely:
- R400, R500
- T400, T500
- X200, X200s, X200 Tablet
- If your ThinkPad system does not exhibit these failures, update your BIOS and Embedded Controller code to prevent this problem from occurring.
- If your ThinkPad system exhibits any of these failures, follow these instructions to reset your ThinkPad system:
- Remove the AC adapter, system battery and CMOS (coin) battery (under the palm rest) for about 30 seconds.
- Reattach the CMOS battery, palm rest, AC adapter and system battery.
- Power yourThinkPad system on.
- If it powers on successfully, then update the BIOS and Embedded Controller code.
- If it did not power on successfully, then have the ThinkPad system board (planar) replaced.
- This issue is resolved with an Embedded Controller update (which is included with the BIOS update). Please use these versions or later: