i have looked in the carminat operating manual, and in the troubleshooting guide, it states :
PROBLEM - After running for some time the system switches off by itself
SOLUTION - When temperatures are abnormally high or low, the system is temporarily switched off to avoid any damage. as soon as the temperatures returns to normal, the system starts up again.
The car may possibly have some kind of faulty temperature sensor.
but is it
1. the temperature of the CD/DVD player (sat nav disc)
2. temperature of the control Unit
3. Temperature of the screen
help. i've almost nailed it.