An Open Letter to the Ford Motor Company on the Ford Fusion Hybrid Braking System

My 2010 Fusion Hybrid crashed today. No, I didn't smash into anything...the electric traction system in my car crashed in the computer sense as I was rolling towards a stop sign. I was left without power brakes. Thankfully this was at ~5 mph so just stomping really hard on the pedal yielded a stop.
As I approached the stop sign in electric drive mode (engine off), my dashboard lit up light a Christmas tree, displaying warning lights I didn't know I even had. The display shouted 'SERVICE ADVANCE TRAC SYSTEM' and my brake pedal went almost to the floor.
To fix this, I did the old IT trick: I turned it off and turned it back on. Problem "solved."
This seems a rather serious failure mode, as without the engine running, there's no vacuum to power the brakes. As the car can run with the engine off up to 45 mph, I'd rather not imagine stopping from that speed sans a brake booster.
Having been around embedded software, I can understand what likely happened. Something "impossible" happened in the PCM (probably a bad read from a sensor caused a divide by zero or overflow), and the electric drive system failed. Still, in a realtime system, a crash like that is unacceptable.
Not quite sure what my next step is, but sending your product to a junkyard lest it kill someone is on the list.  
I've forwarded this to NTHSA for review.

Harold Combs
Georgetown, Texas
140k mile Ford Fusion Hybrid Survivor


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