Help Diagnosing Unintended/Uncommanded Acceleration Issue

Jayman,

The lawyers are always involved now. The poor folks manning the phone lines are given instructions to take info, but to never, never admit that there have been similar reports. They are bottom of food chain, but they can be the first to see a pattern developing. I wonder if the "phone people" are actually in one big room with 100's of work stations? If so they could compare notes or overhear other conversations?

I wonder if there is a problem with the traction control system ABS interaction?

Still, the throttle position being misread for some reason -something stuck-seems more likely(is there a strain gauge in there, or is it strictly position). Like Bob mentioned, the Prius II's have a cheezy plastic casting throttle "thing" (i just looked at it-doesn't inspire confidence) but the 2010's are metal. Makes you wonder why.

Charlie

 

RHD 2008 Prius pedal setup:



Looks like the metal rod clips into a plastic plunger that operates the same sensor assembly.

Coming from a 2001 Ford Focus, I found the brake pedal in the Prius incredibly wide. Of course, that car had a clutch.

 

Mike,
Interesting- my 2006 Prius has a plastic "rod" not the metal rod yours has. I wonder why it was changed?
Charlie

 

It has two hall effect sensors which monitor position.

Tom

 

I've already posted it, but here is the schematic again



Here are possible accelerator pedal sensor DTC's

 

Strictly position-thanks.
Charlie

 

Probably because the problem is so rare and difficult to isolate. However, if a Prius owner with a few bucks happens to get killed due to unintended acceleration, and the spouse retains a lawyer who is straight from hell, I bet after the lawsuit they fix the problem

 

FYI, you can always do an emergency shutdown of the hybrid system: push and hold the Power button for 3 full seconds - the hybrid system will shutdown - system main relay will disconnect the HV battery - transaxle will go into N - power mode will be ACC.

Give it a try when there is no traffic so you will know what to expect. It will not hurt the car, you will still have brake function because of the emergency backup power supply.

 

I hope Toyota reads these forums. The fact a 2006 owner has to trade as he no longer trusts his car, is an omen

 

Yes, or an unintended upside that helps Toyota sell more new cars. Note that he still bought another Prius. It's all upside for Toyota.

 

Yup. If the dealer doesn't sell it to someone else, it goes off to auction. The dealer never looses.

 

I was reading the manual for our 09 NAH and it's suppose to have a EDR or event data recorder. Does the Prius have this? Here's what the manual stated:

The EDR in this
vehicle is designed to record such data as:
c How various systems in your vehicle were
operating;
c Whether or not the driver and passenger
safety belts were buckled/fastened;
c How far (if at all) the driver was depressing
the accelerator and/or brake pedal; and,
c How fast the vehicle was traveling.
c Sounds are not recorded.

 

Wow, that would be great. I would really like to know what happened, even if it was my doing. No one else has mentioned an EDR or "black box," so I assumed that it's not available on a 2008 Prius. But thanks for mentioning that they are available on other cars. I didn't know what you meant by a NAH.

 

Sorry,

Nissan Altima Hybrid = NAH

I was thinking that since Nissan licensed the hybrid technology from Toyota this would have been borrowed as well.

 

Just for reference, it SEEMS like my 2007 Prius has a plastic "rod" as well. It's too dark now to tell for sure, but I felt around, and it's certainly shaped differently from what's shown in that 2008 metal rod picture...