TAG MIL-BOOK 200 Series - Manual (Page 90)

Setup Configuration Utility (SCU) 5-11
HDD Heater
Sets if the system automatically turns on the built-in hard disk drive
heater for low temperature operation. A check mark (
√) indicates
enabled, while underline (_) indicates disabled.
NOTES:
To use the HDD heater feature, the MTCCTRL driver supplied with your computer
must be installed (see chapter 6 for details).
Disable this item to conserve energy when using battery power.