NHTSA Complaint #10345638 — 2010 TOYOTA PRIUS

WAS DRIVING PRIUS 2010 MODEL II WITH BRAKE SOFTWARE APPLIED BY DEALER ABOUT 1.5 MONTHS AGO. TODAY (7/27/2010) I EXITED HIGHWAY AND BEGAN GENTLE BRAKING ON OFFRAMP, AS SUGGESTED BY MANUAL TO MAXIMIZE REGENERATION. ABOUT HALF-WAY DOWN OFFRAMP, I REALIZED CAR IN FRONT OF ME WAS COMPLETELY STOPPED AND THAT I HAD TO STOP MUCH MORE QUICKLY THAN I WAS PLANNING TO. I DON'T RECALL BEING PARTICULARLY DISTRACTED, BUT I CAN'T RULE OUT I NOTICED THE STOPPED VEHICLE LATER THAN I SHOULD HAVE. IN ANY EVENT, I'M NOT SURE HOW HARD I PRESSED THE BRAKES, BUT I RECALL DISTINCTLY THINKING "OH, MY GOD. NOTHING IS HAPPENING" AND 1-2 SECS LATER I PLOWED INTO THE CAR IN FRONT OF ME. THE COLLISION WAS HARD ENOUGH TO CAUSE TEMPORARY PAIN TO THE DRIVER IN FRONT OF ME, BUT NO AIR BAGS WERE DEPLOYED AND THE PRIUS APPEARS TO NOT HAVE MAJOR FRONTAL DAMAGE - HOOD IS BENT BACK AND MAYBE SLIGHT FRAME DISTORTION => THE IMPACT CLEARLY WAS NOT AT THE ~40-50 MPH I WAS GOING WHEN JUST EXITING THE HIGHWAY, SO SOME BRAKING CLEARLY DID OCCUR -- BUT I HAVE THE DISTINCT FEELING THAT MY PREVIOUS CAR (SUBARU OUTBOOK) WOULD HAVE EASILY STOPPED IN TIME. AFTER ACCIDENT, I TESTED BRAKES BY GOING 15-20 MPH IN PARKING LOT AND BRAKING HARD. ALWAYS STOPPED QUICKLY, I'M GUESSING W/100% FRICTION BRAKING. SO BRAKES ARE PROBABLY NOT "DEFECTIVE" IN SENSE OF LOST HYDRAULIC FLUID, ETC... BUT I HAVE NEVER BEFORE EXPERIENCED THE FEELING "I'M NOT STOPPING" EXCEPT ONCE WHEN LOSING TRACTION ON ICY ROAD WITH A NON-HYBRID. THE FACT HAD TIME TO THINK THIS THOUGHT AT ALL PROBABLY MEANS MAYBE 0.5-1.5 SEC PASSED WHILE BRAKING INEFFECTIVE. CHECKED FOR TIRE/SKID MARKS ON ROAD OR EVIDENCE OF STRONG TIRE WEAR AND FOUND NONE, WHILE I HAVE ON OTHER CARS WHEN I HAVE HAD TO BRAKE HARD => PRIUS NOT BRAKING HARD DESPITE EMERGENCY. SEEM TO HAVE BEEN CAUGHT IN TRANSITION BETWEEN REGEN & FRICTION MODE? THIS IS STILL DISCUSSED IN PRIUS FORUMS -- SOFTWARE FIX NOT GOOD ENOUGH!? THIS IS POTENTIALLY VERY DANGEROUS. BTW,CAR WAS IN "ECO" MODE. *TR