Chas2

So after all this time, I think I finally understand why Acura and Honda refuse to swap out the PAX system on the RL and Odysseys. Certainly cost is one issue, but the MID software is probably the main issue. An advisory from Honda reads

"American Honda Motors (which includes the Acura brand) specifically recommends against replacement of the Michelin PAX™ System tires and to do anything [that] can compromise the safety of the vehicle and its occupants."

What is the safety issue? Conventional tires may not be as safe as PAX in a blowout situation, but 99.9% of the cars in the world run on conventional tires.

The advisory goes on to say:

"On vehicles designed to use the PAX System, if the air pressure in a tire drops significantly, a message appears on the multi-information display that tells the driver it is OK to keep driving. This message is given because a PAX tire can be driven on even when it is significantly under inflated or flat. However, this message will appear even if the vehicle is subsequently outfitted with conventional wheels and tires. Driving on under inflated conventional tires can result in a sudden catastrophic tire failure and corresponding loss of control. Additionally, the ride and handling characteristics of the vehicle may be adversely affected since its design was optimized for PAX System tire and wheel assemblies.

"Any person or business that installs a conventional tire/wheel assembly on a vehicle equipped with the PAX System does so at their own risk and is solely responsible for any loss or damage resulting from the modification."

1. While this was never an issue for me, I finally figured out that if you do not regularly drive the vehicle, someone such as my wife, or a friend will not know that there are conventional tires on the car, which can cause a major safety issue if the driver follows the MID advice.

2. All that aside, I also wonder if De-PAXing also becomes a potential liability issue when it comes time to sell the car, and it is possible that you will not be able to sell the car because an original manufacturer designed safety system has been permanently disabled.

3. If you do De-PAX, I wonder if it would be a good idea to keep the original PAX™ system so you can later sell the car with the “as originally equipped” safety system intact.


Any lawyers in the house?

Comments?

Jackzilla

That being the case, best bet is to save the PAX system tires until selling or trading the car. That way nothing is compromised, no liability issue and you can save the cost of a set of PAX tires by running regular tires until a sale.

Still, it is hard to believe that the firmware in the monitor system CANNOT be changed to reflect NON-PAX tires needing to be repaired or replaced immediately. When all is said and done I think it is just $$$$. They just did not want to spend the dollars involved to do the right thing and REPLACE what is a failed system!

The biggest culprit in this whole mess is Michelin for continuing to charge exorbitant prices for a tire system that by their own actions is flawed but which they think the customer should pay the freight. Somewhere this will eventually come back the bite both Honda and Michelin when, with the passage of time, there are NO MORE service facilities to service the tires and owners have no choice but to replace with conventional wheels. Then the law suites will begin.

Jackzilla

A way around the liability issue occurred to me after writing the previous post -- simply leave out the TPMS sensors in standard replacement wheels/tires. It means you'd have to maintain tire pressures to old fashioned way by checking them manually with a gauge, but it would certainly prevent any dangerous assurances to keep driving with an under inflated tire -- which the PAX firmware would suggest if still active.

Thoughts???

dwboston

I think you'll get continuous TPMS warnings in the MID if you get rid of the sensors.

Jackzilla

From actual experience when switching between my PAX tires and the standard set I bought on E-bay, there is no MID warning for the several miles it takes for the system to detect the new set of TPMS sensors. Each wheel location simply shows as blank -- as does the wheel location of the mini-spare when it on the car.

dwboston

But you had TPMS installed, the system hadn't calibrated yet. In the absence of TPMS sensors, you will get either "SYSTEM FUNCTION ERROR" or "CHECK TPMS SYSTEM" errors in the MID.

Jackzilla

It would appear you are correct, according to the owners manual -- although there is no specific notation or warning that the MID will indicate a problem while driving on the mini-spare. What is specifically indicated is that the VSA system is deactivated during mini-spare use. Does the system have some way of knowing the spare is on the car?? Or does it go into this mode when one wheel indicates no air pressure?

In any case, I guess it just boils down to saving some useful life on the PAX tires for when it comes time to sell the RL. I certainly have no intention of spending $2000 or more to replace these suckers when they wear out. And after switching with standard tires a couple of times now, I think the standard wheel/tires are a smoother rolling combination (even if slightly noisier) than the PAX.

Chas2

I think you are right, that I will just save the PAX with some useful life on it, and by the time I sell the car, it may be that the TPMS batteries will have died...so Jack's scenario will play out naturally!

And yeah, I notice a huge difference between the PAX and standard wheels and tires. 92 lbs less of unsprung weight makes a huge difference!

CFoote

I have a comment about this whole PAX thing. Obviously there were cars with the PAX system and those without it. The message that comes up on the display comes up because the car was coded to have the PAX system installed.

Therefore, there must have a way to DECODE the car so that it knows it doesn't have PAX. This of course will require a dealer you have a good relationship with as it will require a call to Honda's techline and someone who knows what they are doing on the phone.

I know with BMW's you can code the car to have certain options -- Park Distance Control, Navigation System, Premium Stereo, etc. All it is is a checkmark next to the option name on the computer screen. The computer then recodes the car and you are off and running.

My point is that there must be a way to disable the messages. If anyone here has a great relationship with their dealer and they are willing to talk to someone knowledgeable on the Honda techline #, they should be able to find a way to disable the PAX messages. All you need to do is tell the car the PAX system is not installed as an option.

Chris

Chas2

I don't disagree with you at all. The trick is trying to find a dealer willing to reprogram this aspect of the car, if it can be done. It is not clear to me if the code is already built into every car, or it is a purpose designed controller module, since PAX MIDs also display menu trees that deal with the ACC and CMBS. If the entire controller feeding the display is unique and not easily programmable, I can see the issue. I certainly would not want to lose my ACC and CMBS functionality. My guess is that it can be done, but it is an expense Honda/Acura do not want to bear.

Considering that non US Honda Legends can also be equipped with LKAS, nose cameras and infrared imaging, I imagine everything is programmable. It probably goes back to some other unknown processes such as a software certification they must do with NHTSA or some agency like that, much like the expensive emissions certification process they have to go through with each engine configuration for the EPA.

HondaV10

Hi guys.

Just this Saturday, I picked up an Acura certified RL Tech originally equipped with PAX tires. The PAX tires have been removed, a spare tire kit was installed in the trunk, and conventional A-Spec wheels and tires have been fitted. TPMS/etc still work... so I just wanted to confirm with you guys, there is definitely a way for the dealer to completely turn off the PAX system in the RL.

dwboston

The PAX system will work fine with regular tires and TPMS. The issue is, what happens when you begin to lose air pressure in one of the tires. The CMBS/PAX RL will still think you have PAX tires on the car and give you a mileage countdown until you need to stop driving on the run-flats. It's not a problem as long as you know that the car has conventional tires, but if it's been traded or sold to a new owner, it could be a safety issue if the person thinks they can keep driving on a flat tire.

Chas2

dwboston is correct. The only issue is when a very low to no pressure situation is detected, the MID will advise you it is safe to drive for 125 miles at up to 50 or 55 mph, which, of course, is not true with conventional tires. That is the part that is not something Honda will reprogram.

CFoote

There was a lawsuit on this whole issue, right? Is it worth contacing the attorney to talk to them about this issue? Maybe they can negotiate with Honda/Acura and get somewhere? Just a thought...

I feel bad for you guys, thats very frustrating. It was a innovative system at the time anyway...

Chris