There is a glitch in the computer program in the ECU, which controls the gear change of the mechanical type automatic transmission. When the driver stops the vehicle without pressing the clutch pedal after driving in the 'D' range, the clutch is disengaged automatically, so it may occur that the vehicle starts to creep if it is stopped on a down hill without the brake applied. The ECU could mistakenly recognise such a condition as a normal driving mode, in which case it will engage the clutch, allowing the vehicle to take off.