Accelerator observations

Interesting, NHW11 accelerator encoder returned for re-work:

http://hiwaay.net/~bzwilson/prius/pri_acc_200.jpg
http://hiwaay.net/~bzwilson/prius/pri_acc_210.jpg
http://hiwaay.net/~bzwilson/prius/pri_acc_220.jpg
http://hiwaay.net/~bzwilson/prius/pri_acc_230.jpg
http://hiwaay.net/~bzwilson/prius/pri_acc_240.jpg

You will notice the lever arm of the resistor assembly is bent so at maximum accelerator deflection, the angle of the nylon bushing can easily 'jam' in the slider. I noticed the 'sticky' position while testing the accelerator after cleaning the slider contacts. Given a little dust between the nylon bushing and the metal slider or paint or other sticky debris, the accelerator could stick in this position. This would lead to an exciting driving experience.

The lever arm looked to be substantially strong piece with re-enforcing bend through the center. But I was surprised at how easy it was to straighten it. Regardless, another non-linearity in the resistance range disappeared once the arm looked more like 90 degrees.

I'll put this repaired accelerator in my car in the morning and ship the other one out. But now I see how a bent lever arm could lead to a stuck accelerator. I understand the NHW20 uses a similar mechanical configuration.

Bob Wilson

 

Not a clue. Perhaps this is a part Toyota got from another supplier. The customer had noticed it too when he took it off his car.

Already done and going in my car this afternoon. But I am going to follow-up with a note to Toyota America and possibly a notice to the NHTSA. This potentially is a safety issue.

Bob Wilson