Audio-HVAC subdisplay does not work properly

1. Check the clock. Reset if necessary.

Does the clock reset?

YES | - | The system is OK at this time.■
NO | - | Go to Step 2 .

1. Check for an open or short to body ground between subdisplay unit 10P connector terminal No. 4, No. 5, No. 6, No. 7 and navigation unit connector A (10P) terminal No. 4, No. 5, No. 6, No. 7.

Are the circuits OK?

YES | - | Replace the navigation unit.■
NO | - | Repair the circuits.■