Parking Brake Failure and still on long road trip

[bigx5er]

We drove our 2012 X5 3.5i from Minneapolis to Las Vegas. Made it to Vegas, but a major adventure with the parking brake and I could use any advice on the thing.

When we were in Denver, it started to rain like crazy and I-70 had a good two inches of rain on it, plus deeper puddles. The red parking indicator started to flash, then the steady yellow with the parking symbol in the center dashboard display. The status showed "Parking Brake Failure".

Once we got up into the mountains and it stopped raining, the light went off. Then is started to rain again and this time the light stayed on for over and hour.

Now when ever it starts to rain (throughout Utah), the red park light flashes and the steady yellow park light alternate on and off. When the red light flashes, the dong sound keeps going off. We drove over and hour straight with that thing going off.

I tried to manually release the parking brake and it didn't help.

Anything I can try? I'm a long way from home.

Thanks