Had an at fault accident - braking anomaly - like hit sheet of ice

Well, the good news is no one got hurt. The bad news is I am charged with at fault accident and worse yet, when I get the front clip of my prius rebuilt I'll never feel safe driving the car again even if it looks as good as new.

My driving record is good. My last accident was 20 years ago. My Prius is an 08' with 75K miles and good tires. Just inspected last month by toyota dealership.

Here's what happened -

Driving down asphalt road that was slightly damp from drizzle. It was about 58 degrees out and around 7:30 PM so it was dark. Was very much aware of my speed as I was concerned about a deer crossing my path and hitting it - that's why they call where I live bucks county. I was going about 25 miles/hour. I could clearly see an SUV stopped about 80 feet away at a stop sign. I put my foot lightly on my brake pedal to begin a slow controlled gradual stop. This kind of braking encompasses about 99.5% of the braking maneuvers we all do every time we drive. What happened next still has me puzzled and very much concerned. What I experienced next can best be likened to hitting a patch of black ice and completely losing traction. But if that was not strange enough, there was no pulsing in the brake pedal like you would expect in this situation from an ABS equipped vehicle. I did not release pressure on the pedal but pressed harder. Nothing changed. I kept thinking that any second the tires would grip the road. When they did not, I realized at that point I had two choices - pull into the left lane and avoid hitting the rear end of the SUV. I thought better of this because there was a good chance of having a head on with a car that may have come around the corner. Also, I had a likely chance of continuing to my quiet glide into the intersection where I could have possibly been broad sided and killed. So I braced for impact with the SUV at around 25 MPH - the same speed I was traveling when I originally depressed the brake pedal some 70 feet back.

The back of the SUV probably had about 800-1000 dollars worth of damage. I have not had my prius estimated yet but if it wasn't at least $5000 i'd be surprised. I was amazed that it seems perfectly fine driving.

Needless to say, I am grateful no one was hurt but am very concerned about how the car failed to handle correctly. I am also angry that I now have an at fault accident that I feel was not my fault. I told my insurance company what happened but they really were not that interested. They said only the dealership could determine if something malfunctioned and I should have them look at it. They didn't really care if I followed up with them about it or not - at least that is the way it seemed. I'm sure they hear all kind of pathetic stories where their insured try to minimize their contributing mistakes leading to an accident in hopes of lessening surcharges to their renewal premiums.

In my mind it would almost be better if I could find fault in something I did or didn't do to cause the accident. This is because I had hoped to hold on to this vehicle for at least another 4-5 years and figuratively drive it into the ground. When I get this back from body shop I'll need to think about whether I'll ever trust this car again and may decide I need to get something different.

Do any of you know whether a fault in the brake system will cause an error condition to be stored and retrieved using scan guage or by some other means. I'd really like to know what went wrong. If so, do you believe dealership would be straight with me if they found a problem ? If a problem was found, would Toyota in any way be responsible for what happened ?

Thank you all for reading my post and thank you for any technical expertise you can share with me. I already know about the latency between regenerative braking and friction braking. This may or may not have started like that condition but it did not resolve in any thing close to a timely manner. Forgive me for cross-posting this in other gen II forums.

 

It had been raining most of the day but had let up to a drizzle by nightfall but I am familiar with what you are saying. Thanks

 

I will try to get Toyota regional or corporate to look at it. I'm guessing the last thing they want to do is find another problem but I would trust them more than the dealership to do a responsible inspection.

 

Actually just adjusted them for fall weather temperatures. I had them at door placard recommendation 35 front and 33 rear. Should not have been a factor but you are right - lots of folks do push for better mileage. I used to do that but the trade off in slightly better mileage didn't seem worth it to me in harshness of ride. When I did have pressures higher I'd never do more than +3 lbs in front and back. Maybe that's why my mileage was not that much better at higher pressures.

 

Thanks - I was thinking about that. I can say with some certainty that I did not have any lateral (left/right) slipping but then again I did not turn the wheel much past dead center. I do not know what would have happened if I had tried to shift lanes - I didn't attempt that.

 

No the integrity were really scary tires. I have Hankook H727. Can't give you tread depth but they look like they could run another 20K miles. Been happy with how well they have performed and held up.

 

No air bags were deployed. I did not stand on the brake pedal but applied significant pressure. Was it 112 pounds - I do not think so. If I had to guess I say it may have been closer to 80 lbs but I really can't say for sure. I will definitely follow up with anything I learn in the near future.

 

There is one thing that I did not mention and I just remembered. About 3 weeks prior to this happening I had my MFD loose communications with all my peripherals - blue tooth, climate, audio, etc. It only happened that one time and corrected after shutdown and restart of the car. I was able to bring up the diagnostic screens on the MFD subsequently and didn't know what all the hex error codes meant but some of the more discernable descriptors seemed to indicate LAN issues (i think that's what the description was). I took that to be similar to computer local area network communication errors. Was this a precursor to anything that happened last night - I don't know but it was coincidentally the only time in 4 years that either of these two types of anomalies have happened MFD and traction issues (the later being about 3 weeks after).

 

I'm going to call it a night but will try and get some photos up of the front of car and the tire condition tomorrow if I have a chance. Thank you all for taking an interest in my problem. Hopefully it's just an isolated incident which hopefully can be explained if/when I do in fact get Toyota to inspect data and braking system. Stay tuned and check back for some pics of a really ugly front end.