In 2014 Tamiya changed their kit ESC to the TBLE-02S model. The speed controller features a low-voltage cut-off function, but it is set to 4.9V -- much too low for LiPo batteries that most RC enthusiasts use nowadays.
However, by adding a single resistor we can modify the cut-off voltage to a LiPo-safe 6.0V or 6.3V.