With all this social distancing and shielding, my XF has been sitting idle for a couple weeks. I started the car up just fine and the battery tests strong, but at some point, I got the 'park brake fail' warning and now the e-brake will never engage.

I disconnected the battery for a couple minutes, then reconnected, and get the IP instructions to apply foot brake, and then e-brake, but the next thing I see is the original failure warning.

Any advice or other ideas for how to clear?

 

Fair chance it's not getting enough peak current from the battery.

 

Hmm, any trick to that? Like having the car be on for a period of time first?

I feel like the voltage regulator would keep things pretty constant.

 

Usually a sign of a failing or low battery.

 

Fwiw the actuator needed replacing.