Had an Alhambra that used to freeze and you had to stop, turn off, lock and unlock the doors then turn ignition on and press power button for 20 seconds, took about 2 minutes to reboot.
Regarding the Grand Pic, I have one and have affected a fix for the control unit problem, it’s caused by overheating, I removed the twin vent unit above and using a dremmel cut two 3×1″ holes in the bottom of the vent pipe that sits above the back of the screen, allowing the heat from the back of the head unit to escape through the twin vents above, not had a problem since I did it a year ago.