How long have you waited for it to restore? I'd give it about 15 minutes to come back. Then:
1. Did you try rebooting the main display? (Hold both scroll wheels for about 10 seconds). After it restarts, give it a few minutes to get the signal again.
2. If that doesn't help, do a search here and there's a fuse you can try pulling. Wait a few minutes after it's pulled, then replace it.
3. If 1 and 2 didn't fix the issue, then call Tesla.