The Straight Dope

Go Back   Straight Dope Message Board > Main > General Questions

Reply
 
Thread Tools Display Modes
  #1  
Old 11-20-2010, 06:46 PM
Johnny L.A. Johnny L.A. is online now
Charter Member
 
Join Date: Jan 2000
Location: NoWA
Posts: 49,144
Toyota Prius traction control override

From another thread:
Quote:
Originally Posted by Spoons View Post
Quote:
Originally Posted by Johnny L.A.
The Prius's wheels are driven by electric motors. As part of the traction system, if a wheel begins to slip power is shut down to it. You can see the problem.
I can, but I have what is probably a dumb question: is there any way to override that "shutdown on slippage"? It seems a silly feature to have on a car that will be used in cold climes; I wonder why the Prius engineers would include something like that if they expected sales in places that experienced winter.
Is there a way to override the traction control in a (2005) Toyota Prius?
Reply With Quote
Advertisements  
  #2  
Old 11-20-2010, 07:06 PM
davidm davidm is offline
Charter Member
 
Join Date: Mar 2002
Location: Near Philadelphia PA, USA
Posts: 6,239
Quote:
Originally Posted by Johnny L.A. View Post
Is there a way to override the traction control in a (2005) Toyota Prius?
My Insight has a button to turn off traction control. So did my previous car, a non-hybrid Saturn.

A cursory googling seems to indicate that you can't turn it off on a Prius.

http://www.google.com/search?q=prius...ient=firefox-a

This page: http://wiki.answers.com/Q/Can_toyota...ol_be_turn_off
claims that you can but, considering the described procedure, I think the poster may be full of crap.
Quote:
To disable traction control on the prius:
1) Turn the car to ignition by pressing START twice without pressing the brake.
2) Floor the gas pedal two times (two full top to bottom pressings)
3) Make sure the parking brake is on, and while pressing the brake pedal put the car into NEUTRAL
4) Again press the gas pedal two times
5) Push PARK and press the gas pedal two more times
6) Now put your foot on the BRAKE and press START one time while holding the brake down.

Last edited by davidm; 11-20-2010 at 07:09 PM..
Reply With Quote
  #3  
Old 11-20-2010, 07:26 PM
Johnny L.A. Johnny L.A. is online now
Charter Member
 
Join Date: Jan 2000
Location: NoWA
Posts: 49,144
Thanks for the hint, davidm.

I found this (emphasis original):
Quote:
WARNING: The shop manual apparently states in no uncertain terms that this procedure must NOT be used to drive the car as damage to the transmission could occur due to traction control being defeated.

Follow the sequence below (quickly - within 60 seconds)
  • Set Ign switch to ON, not READY (Power button twice, no brake)
  • While still in "P" fully depress the gas pedal two times.
  • Select "N" fully depress the gas pedal two times.
  • Select "P" fully depress the gas pedal two times.
    (LCD display will indicate a !Car! in upper left corner of screen)
  • Turn key directly to "start" to start the engine (brake+start button)
It forces the ICE to run continuously and defeats the traction control system. Normal operation returns after turn off and reboot. Unlike EV-Mode this is strictly a diagnostic function and should not be used under normal situations.
Reply With Quote
  #4  
Old 11-20-2010, 07:33 PM
GreasyJack GreasyJack is offline
Guest
 
Join Date: Feb 2008
This doesn't strictly answer your question, but your understanding of how traction control works isn't quite right. The TCS doesn't cut power (for one thing, many TCS-equiped vehicles have old-fashioned cable throttles and so can't cut power), but applies the brake on the one spinning wheel, which will prevent all the power from being sent to that wheel by the differential. So it sort of acts like a limited-slip differential.

Now, this is the stuff of rampant debate, but generally there's no reason to turn the TCS off, except maybe to do burnouts or spin doughnuts. The only exception is maybe if you agressive truck-style tires, turning the TCS off and spinning your tires might help you "paddlewheel" out of mud or snow. But for the kinds of tires you've got on a Prius, there's (arguably) really not going to be a situation in which you'll have no traction with the TCS and some without.
Reply With Quote
  #5  
Old 11-20-2010, 07:41 PM
GaryM GaryM is offline
Charter Member
 
Join Date: Jun 2000
Location: St. Louis, MO 50mi. West
Posts: 3,389
Quote:
Originally Posted by GreasyJack View Post
This doesn't strictly answer your question, but your understanding of how traction control works isn't quite right. The TCS doesn't cut power (for one thing, many TCS-equiped vehicles have old-fashioned cable throttles and so can't cut power), but applies the brake on the one spinning wheel, which will prevent all the power from being sent to that wheel by the differential. So it sort of acts like a limited-slip differential.
I had a 2004 Prius and now have a 2010. On those two models the power is cut for traction control. This does make it difficult to ascend a snow covered or iced slope in some cases. It's also difficult to rock your self out of a snowy parking place as well.
Reply With Quote
  #6  
Old 11-20-2010, 07:44 PM
Johnny L.A. Johnny L.A. is online now
Charter Member
 
Join Date: Jan 2000
Location: NoWA
Posts: 49,144
Quote:
Originally Posted by GreasyJack View Post
This doesn't strictly answer your question, but your understanding of how traction control works isn't quite right.
Apparently I was confusing the power recovery system at the wheels with motors that drive them, based on the animation on the nav screen.

Nevertheless, the car will not move (from a stop) in snow. Whether power is cut to the wheels, or brakes are applied to them, there is no motive force.
Reply With Quote
  #7  
Old 03-27-2013, 07:30 PM
aajaay aajaay is offline
Guest
 
Join Date: Mar 2013
traction control overide light comes on and beeps

I drive and the light comes on and beeps! I lose power and my car slows and it is very dangerous the drive conditions are normal. this started when I had a low tire I changed it to the spare. I immediatly had the spare replaced the car did fine on the way home I parked it then went out for an errand and it started doing the same thing. the tractino control light come on and it beeps and I lose power at first it was only at speeds over 30 miles per hour seems to be the rule.
Reply With Quote
Reply



Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 09:05 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.

Send questions for Cecil Adams to: cecil@chicagoreader.com

Send comments about this website to: webmaster@straightdope.com

Terms of Use / Privacy Policy

Advertise on the Straight Dope!
(Your direct line to thousands of the smartest, hippest people on the planet, plus a few total dipsticks.)

Publishers - interested in subscribing to the Straight Dope?
Write to: sdsubscriptions@chicagoreader.com.

Copyright 2013 Sun-Times Media, LLC.