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Tire Pressure numbers that show during shut-off ? ?

I am a new owner of a 2010 in Cypress Green, which I had to drive very far to get by the way... And am loving it so far.

When I shut off the car, I get 5 Tire readings on the small monitor.

Now, here's the kicker, in the book it says that the tire numbers are shown on that screen in "no particular order" ... well... obviously that's not true, and I cannot imagine why Toyota wouldn't want me to know WHICH tire had less air in it than the others. DUH...

So I have been watching these numbers daily. There are 5 numbers from top to bottom, they usually read something like this:
34
36
38
36
38
When it's colder, they vary a little, but those are usually my readings.

My guess is that the first number is some sort of recommendation, or perhaps a spare? and that the last four are the tires, and since the order never changes... I was wondering if anyone has figured out which number on the reading corresponds to which tire?

If it were nicer outside, I would put air in only one, and then test it out one by one... but since hybrid owners are so sensitive and on top of their tire pressures, I am assuming one of you has already easily figured this out.

I want to just pop some air in my 36s to get them all to around 38 on my gauge.

I'll keep checking back to see if anyone can answer this for me... Thanks
 

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:facepalm: The least they could have done was put RF, LF, RR, LR, and S beside the corresponding tire. I'd certainly call or write Toyota corporate and provide them with your observation.
 

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The trouble is when yhou rotate your tires. The RF system monitors the signal from the TPMS in each wheel so it's position can change on the vehicle after a rotation (The top one 'usually' is the spare). To my knowledge the system isn't capable of telling you the actual position on the vehicle the tire is at once the tires get rotated.

Maybe a service tech can confirm this, but this is what I was told.
 

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steamn2
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steamn2

The posts about tires and driving techniques beg the question, which is SAFETY. My case in point is going up steep, snowy mountain road here in western NC I lost traction, then power to all 4 wheels shuts off - no power from gas engine nor battery motors. HH skiddded sideways and then slid about 200 ft, still sideways, down my mountain road. Very scary, absolutely no control or ability to turn into skid under power! I lived in western MT for 11 years and know how to drive in snow. So, I tried again from bottom with more momentum - same result. If someone had been coming down while I was sideways, a T bone or being knocked off the mountain would have been likely. Parked it on road side and walked up the mountain.

Safety aspect questions: (1) What if I get snow tires and/or chains, and the same result happens again on steep mountainous road; and (2) What if I'm on flat highway with regular tires and hydroplane? Answer to both, SOL. There shouldn't be a need to find a work around - snow tires, etc. This shut off of wheel power post traction loss is a design or electronics flaw that should be fixed before someone is killed or seriously injured.

I've contacted Toyota, the NHTSA, the NC Attorney General's Consumer Protection section and started the complaint process. Am not optimistic about near term relief but will post pertinent updates.
 

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Safety aspect questions: (1) What if I get snow tires and/or chains, and the same result happens again on steep mountainous road; and (2) What if I'm on flat highway with regular tires and hydroplane? Answer to both, SOL. There shouldn't be a need to find a work around - snow tires, etc. This shut off of wheel power post traction loss is a design or electronics flaw that should be fixed before someone is killed or seriously injured.
Unfortunately, the hybrid-powered Highlander does not have a button to turn off the stability control and traction control systems, and why I do not know? :confused: Turning off VSC/TRAC in the gas-powered Highlander in snow and ice is the difference between night and day: no traction in those conditions versus traction, primarily by preventing the engine from being dethrottled. You know what the irony is to your observation above? It's that we had a member here on TN threaten me and TN with legal action for describing to other owners about shutting off the Highlander's VSC/TRAC system, even though Toyota provides owners with the ability to turn it off at the owner's discretion due to road/traction conditions, as outlined in the owner's manual. :disappoin :facepalm: Oh, before I forget let me offer the disclaimer to owners out there who do have the switch to use it at your own risk. Lawyers and Nanny State ninnies will be the death of us.
 

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Agree ... this shutoff of all 4 tires in snow ... along with another thread about this Hybrid being complete junk for towing a boat out of water is terrible.

Toyota deciding to remove out ability to determine whether AWD activate, or being able to toggle the TRAC/VSC is complete rubbish.

I still believe anyone driving in winter condition, should get winter tires.
But why can't we have a switch to determine when to activate all 4 wheel in low speed condition?

Is that the point of dragging along an extra set weight to power the rear wheel as needed? If that's not the case or point, then what is the point of 4wd when it only uses 2?
 

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RonThompson1 - I support you 100%.

Toyota at least needs to have an OFF switch. If they fear litigation, they will get sued anyway if a T-Bone incident occurs.

Your situation is the worst I have read anywhere. All four tires losing traction to the point of sliding off-angle and no power returned to any of the tire. That is unacceptable. It is like flight electronics detecting a flat spin and automatically respond by pointing the nose down and pop the after-burner even at 5000-ft. Saying it is "stupid" is being generous.

Toyota needs to change its software so that if all four wheels have the potential to lock and result in total loss of control, the software must revert and let the tires spin where it can at least at low speed. This is not difficult to do.

I will see what owners like me can do to also file a sort of "Friend of Complaint" type report.

In the mean time, while we await Toyota's response, if ever, it is highly unlikely that high quality snow tires will run into trouble. In the worst case, chains should really solve most normal hard-surface snow and ice problems. If chains cannot solve the problem, then the conditions are so bad, not even a 4x4 with locked differential should try.

I do really want Toyota to make this software fix, if it is only a software fix. Someone will get hurt sooner or later and Toyota will just suffer another black-eye anyway. If it proactively resolves this design flaw now, it at least gets a neutral response if not positive. At least it will not get yet another negative.
 

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steamn2
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steamn2

Thanks for the moral and "Friend of Complaint" support.

Some asides: (1) Posted only 2 questions/scenarios re: safety when power shuts off after losing traction, am sure there are many other potential, similar situations; (2) Have frequently used snow tires/chains in MT and know when/where to stay off roads/mountain sides that are too steep, etc - in this case two 4WD pickups went up the mountain past me with no problems; (3) This wasn't the situation of going from AWD to 2WD, it was from AWD to no wheel drive; and (4) Explained fiasco to service mgr at local Toy dealer and asked about ability to turn off TRAC/VDIM, answer was no dice.

Bought the 2009 HH for the AWD as replacement for old Explorer with 4WD and for the increased MPG during Cash for Clunkers. Boy, was that a bad decision! If AWD is not there when you need it (i.e., loss of traction on one or more tires), then Toyota is blowing smoke up the world's backside about the HH's capabilities.

Bottom line: I still think I'm SOL.
 

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Sorry about that RonThompson1, it is really unfortunate.

This is likely caused by the limit of Toyota's software prowess. I can understand how someone designing the software just gave up on the last boundary condition: "Losing all traction". He or she probably said, "It can never happen." I have seen this in younger engineers building Mission Critical systems.

Toyota failed to appreciate that in mission critical systems where lives are at stake, there is no such thing as it can never happen. If one can think of it, it probably will happen and there must be a solution. Even graceful failure is a viable solution in some cases. In our case, having four wheels locked up causing a slide is not graceful by any means.

At the minimum, Toyota needs to revert to manual control. Shut off the darn thing at a certain speed while tires are spinning and let us work our way out of the situation. When all else fails, rely on the driver.

In case a Toyota Rep is lurking here like in the other Forum, DO YOU GET THE HINT? It is going to come back to bite Toyota when we find one or more crash incidents due to this boundary condition!
 

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Thanks for the moral and "Friend of Complaint" support.

Some asides: (1) Posted only 2 questions/scenarios re: safety when power shuts off after losing traction, am sure there are many other potential, similar situations; (2) Have frequently used snow tires/chains in MT and know when/where to stay off roads/mountain sides that are too steep, etc - in this case two 4WD pickups went up the mountain past me with no problems; (3) This wasn't the situation of going from AWD to 2WD, it was from AWD to no wheel drive; and (4) Explained fiasco to service mgr at local Toy dealer and asked about ability to turn off TRAC/VDIM, answer was no dice.

Bought the 2009 HH for the AWD as replacement for old Explorer with 4WD and for the increased MPG during Cash for Clunkers. Boy, was that a bad decision! If AWD is not there when you need it (i.e., loss of traction on one or more tires), then Toyota is blowing smoke up the world's backside about the HH's capabilities.

Bottom line: I still think I'm SOL.
Swap out to the gas-powered Highlander. Pretty much all the owners rave about its performance in snow, ice, mud, sand, boat ramps, whatever....myself included. I know it's an unlikely option, but if you really like the other aspects of the vehicle its just one of many options.
 

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TrailDust - easy for you to say. There's already a lot of money already invested in purchasing our vehicle already.

Many here purchased based on very informed dealership / sales person who convinced us the AWD benefits combined with Hybrid in this car. Yes, best of both world ... apparently not.

That as currently realized, is not really the case. The Highlander Hybrid's 4WD-i isn't behaving like the advertized 4WD nor is it "i"ntelligent.

They just need to provide a software over-ride, and a switch to deactivate VSC/TRAC in low speed situation. Or a button to lock on 4wd in low speed situation.

This car could have been a fantastic car, except for the software and over-ride limitation. Toyota just isn't very competent with their programming prowess.

I don't mind letting the computer do the thinking if it was well thought out, but Toyota's programming skill is limited, so they should relinquish absolute control, and let the driver decide for the best situation.
 

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TrailDust,

Thank you for the heads-up on the "turn OFF" situation. I remember seeing that in another Forum way back in 2006 and got exactly the same advice.

RonThompson1 - Sorry to ask this again but do you run dedicated snow now? Or do you use all-season that is labeled snow+mud? Dedicated snow may be a viable solution. If you have tried this, then please ignore.

I grew up in MI and have taken our HH on dedicated snow all the way back to MI to visit my family over several Winter holidays. It has not yet given us problems even with MI's snow and ice. I would not use all-season snow+mud in MI winter though. We take the Salt Lake route through Jackson, Cheyenne and then on into MI. I would not drive through those areas without dedicated snow treads, especially the Rockies stretch.
 

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I did manage to nearly get my 2006 4wd-i HH (with Blizzack snow tires) completely stuck recently, driving into deep unplowed snow that had it on the verge of being high centered up on the snow. What I found was that while it had a 100% throttle VSD shut-down while trying to go forward, interestingly it would still very slowly spin the wheels in reverse (electric power only) if I held the throttle down whith shifter in R. It also worked very well to rock the car forward and backwards with the shifter mechanism, quickly throwing it between R and D, much easier/faster shifting in the hybrid PSD than with a "conventional" auto tranny that has an actual mechanical shift-linkage mechanism.
In the end, I had to get out and spend a couple minutes with a shovel digging out around the wheels to clear away snowpack and get it some traction, then I was able to reverse out of my predicament.
 

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You can now disable TRAC/VSC

Thanks for the moral and "Friend of Complaint" support.

Some asides: (1) Posted only 2 questions/scenarios re: safety when power shuts off after losing traction, am sure there are many other potential, similar situations; (2) Have frequently used snow tires/chains in MT and know when/where to stay off roads/mountain sides that are too steep, etc - in this case two 4WD pickups went up the mountain past me with no problems; (3) This wasn't the situation of going from AWD to 2WD, it was from AWD to no wheel drive; and (4) Explained fiasco to service mgr at local Toy dealer and asked about ability to turn off TRAC/VDIM, answer was no dice.

Bought the 2009 HH for the AWD as replacement for old Explorer with 4WD and for the increased MPG during Cash for Clunkers. Boy, was that a bad decision! If AWD is not there when you need it (i.e., loss of traction on one or more tires), then Toyota is blowing smoke up the world's backside about the HH's capabilities.

Bottom line: I still think I'm SOL.
Hey Robthompson1,

You can now disable the TRAC / VSC - I've just written up the proceedure to do so on demand.
 

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In another forum, one member wrote that the reason the HH has such an aggressive traction control system is the fact that electric traction motors burn out if allowed to spin the wheels for any significant length of time, so the system is designed to immediately shut down power to the wheels if they spin. That would explain the difference in performance between the HH and gas Highlanders.

Again, good tires do allow the system to work very well, in my opinion.
 

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In another forum, one member wrote that the reason the HH has such an aggressive traction control system is the fact that electric traction motors burn out if allowed to spin the wheels for any significant length of time, so the system is designed to immediately shut down power to the wheels if they spin. That would explain the difference in performance between the HH and gas Highlanders.

Again, good tires do allow the system to work very well, in my opinion.
That would make the rear motor ... umm ... useless ....
Which would make the claim of 4WD a complete sham.

Yes, I just look through information and found that the rear motor is significantly smaller than the main electric drive motor (mg2?).

Toyota had set our expectation too high by advertising 4WD on a car that really a 2WD with rear electric assist motor that only comes on whenever it thinks it needs to be on (which isn't very often).

Besides that, the rest of it seems to be good enough for me to still buy it.

However, if I only know what a fake this 4WD-i really was, I would have opted for 2WD and save some money on gas.
 

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I don't believe it's a case of the rear motor burning out at all...it's just how traction control works. In essence, traction control reduces power to the wheels when tire slippage occurs to give the tires an opportunity to bite again. On some vehicles this is done by retarding the ignition timing and on others by just closing the throttle. What is not correct on either gas or hybrid Highlander models is the fact that the traction control software algorithm is poorly implemented allowing ALL POWER to be lost and eliminating any ability to move the vehicle and creating a safety hazard. I have to believe this is why the bypass was put into the gasoline vehicles. The traction control bypass needs to be present in the hybrid models as well. IF anyone experiences loss of vehicle control due to this poor implementation of traction control then it should be reported to the Feds ASAP...at this time they are listening.

The 2WD bypass that JoeBoxer posted is a great workaround and should help in 98+% of situations. However, this is just a band-aid to another poorly implemented Toyota feature...
 

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I also doubt that the reason is to prevent electric motor burnout. They could just as easily have monitored the motor speeds and cut power if it gets too fast while encoutering slipping. The electric motors are really pretty robust and have plenty of torque capacity, I just dont see that they are that vunerable and fragile. It would also be easy enough for toyota to incorperate a temp sensor and shut them down if they get too hot if that were a worry.
On my other car, (an audi), AWD traction control is implimented by having the ABS system kick in and start applying brake to any wheel that starts spinning, this help to route torque to the remaining wheels that still have traction, no throttle shutdown needed for traction control when implimented that way. Wish toyota would follow suite!


I don't believe it's a case of the rear motor burning out at all...it's just how traction control works. In essence, traction control reduces power to the wheels when tire slippage occurs to give the tires an opportunity to bite again. On some vehicles this is done by retarding the ignition timing and on others by just closing the throttle. What is not correct on either gas or hybrid Highlander models is the fact that the traction control software algorithm is poorly implemented allowing ALL POWER to be lost and eliminating any ability to move the vehicle and creating a safety hazard. I have to believe this is why the bypass was put into the gasoline vehicles. The traction control bypass needs to be present in the hybrid models as well. IF anyone experiences loss of vehicle control due to this poor implementation of traction control then it should be reported to the Feds ASAP...at this time they are listening.

The 2WD bypass that JoeBoxer posted is a great workaround and should help in 98+% of situations. However, this is just a band-aid to another poorly implemented Toyota feature...
 

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steamn2
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Update: I'm still using the A/20s, ~10K miles, that came on the HH. Toy case mgr responded to my complaint and said the incident had to be replicated by a dealer tech for further investigation to take place. Took it to dealer and was told the same. My question to both was who in their right mind would want to drive the HH up a snowy, steep mountain road, lose traction, lose power to all 4 wheels, have it skid sideways and then slide, still sideways, 200 feet down the mountain? Probably should put snow tires on but am hoping to get similar conditions so dealer service mgr can duplicate incident on my mountain road. Yeah!

Have filed a formal complaint with NHTSA and am waiting (how long?) to hear back from them. Same with NC AG's office of Consumer Protection.

Thanks to JoeBoxer for TRAC/VSC turn off procedure.
 
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