TPMS Problems
#11
Re: TPMS Problems
Are you sure the donut doesn't have a sender in it.....I'm thinking it does. Could the 6 wheels be causing the confusion???
I swapped out all 4 wheels for mounted studs with the TPMS in the spare set. Got the warning on the way home (with 9 tires in/on the car), and the next day. Not again, and not when I switched to summer tires (which I did at home, so it did not have any time when all of them were in the car again).
I swapped out all 4 wheels for mounted studs with the TPMS in the spare set. Got the warning on the way home (with 9 tires in/on the car), and the next day. Not again, and not when I switched to summer tires (which I did at home, so it did not have any time when all of them were in the car again).
When I swapped in my new full sized spare, I stored the removed wheel away from the vehicle, so at no time where there more than four wheels and a donut spare on the vehicle.
I really think I have a faulty TPMS sender and I'm going to mount the suspect wheel back on the FEH within the week. But thanks for the good ideas and I'll let you know what develops.
#12
Re: TPMS Problems
Cany anyone confirm the 2008 16" is the same size as previous years? IE as in bolt pattern and similar width. I want a full size spare, but not ready to shell out over $300 from a dealer for one.
#13
Re: TPMS Problems
Here's what I learned that might be useful to someone. But remember that I don't personally know any of this to be accurate:
1) The low pressure trip point at which the warning illuminates is supposed to be 29 to 32 psi.
2) The onboard computer stores the location of the tire reporting low pressure, and also the temperature of the tire.
3) The system has to be "retrained" if a tire is moved or tires rotated, but they are unclear as to how this is to be done. (My belief is that it must be automatic and not require a technician to do anything)
4) A drive time of over 20 minutes at a speed exceeding 20mph is required for the system to read data from the tires. (I believe this to be true as it explains why I never get a TPMS warning in city driving, but always get it about 20 minutes into a freeway trip)
That's it. I'm supposed to try to get the problem to reoccur over the weekend and bring the vehicle in Monday to see if they can read the codes.
#14
Re: TPMS Problems
Don, thanks for the update.
I also went into the dealer for an oil change and asked them to look into that. They came back and said that the tire pressures were off and that's why I get intermittent sensor triggering. BUT, I have all four tires at 41psi!!
Unless the sensors triggers on over-pressures as well as under-pressures, I think the dealer didnt know what they are talking about.
Your point 4 seems to jive with when I see it triggers...usually somewhat into a freeway trip. I'll have try and keep track next time I'm on the freeway.
I also went into the dealer for an oil change and asked them to look into that. They came back and said that the tire pressures were off and that's why I get intermittent sensor triggering. BUT, I have all four tires at 41psi!!
Unless the sensors triggers on over-pressures as well as under-pressures, I think the dealer didnt know what they are talking about.
Your point 4 seems to jive with when I see it triggers...usually somewhat into a freeway trip. I'll have try and keep track next time I'm on the freeway.
#15
Re: TPMS Problems
Don, thanks for the update.
I also went into the dealer for an oil change and asked them to look into that. They came back and said that the tire pressures were off and that's why I get intermittent sensor triggering. BUT, I have all four tires at 41psi!!
Unless the sensors triggers on over-pressures as well as under-pressures, I think the dealer didnt know what they are talking about.
Your point 4 seems to jive with when I see it triggers...usually somewhat into a freeway trip. I'll have try and keep track next time I'm on the freeway.
I also went into the dealer for an oil change and asked them to look into that. They came back and said that the tire pressures were off and that's why I get intermittent sensor triggering. BUT, I have all four tires at 41psi!!
Unless the sensors triggers on over-pressures as well as under-pressures, I think the dealer didnt know what they are talking about.
Your point 4 seems to jive with when I see it triggers...usually somewhat into a freeway trip. I'll have try and keep track next time I'm on the freeway.
The other annoying (and ignorant) thing they insist on doing is lowering the tire pressure to 35 psi and telling me that 40psi is too high.
You aren't by any chance going to Barber Ford in Ventura are you?
#16
Re: TPMS Problems
I go to Heritage Lincoln/Mercury Dealer down here in Irvine/Tustin. They're a decent outfit...very professional, but on occasion they miss a few things.
#17
Re: TPMS Problems
Probably just not as diligent. I just got my oil changed at my dealership last week. When I told the service advisor I keep 42lbs in the tires I might as well have told him we didn't land on the moon from the look on his face. And of course, when I got the car back I pulled out the gauge and they were all back to 35.
#18
Re: TPMS Problems
But it's hard to believe that I would have to have the dealership retrain the system every time I rotate the tires.
One possibility is that the system has to be initially "trained" so that it knows what TPMS sensor ID's are present from the factory. If another sensor is introduced, as in adding a full sized spare, then "training" of the system is again required to make it accept that sensor ID.
I'm going back to the dealer tomorrow and try to get an answer to all this. It's discouraging that the Ford techs don't understand this system at all.
#19
Re: TPMS Problems
I did a freeway trip today of more than 30 minutes and the TPMS warning never came on. That would seem to indicate that "retraining" the system last Friday at the Ford dealer has fixed the problem.
But it's hard to believe that I would have to have the dealership retrain the system every time I rotate the tires.
One possibility is that the system has to be initially "trained" so that it knows what TPMS sensor ID's are present from the factory. If another sensor is introduced, as in adding a full sized spare, then "training" of the system is again required to make it accept that sensor ID.
I'm going back to the dealer tomorrow and try to get an answer to all this. It's discouraging that the Ford techs don't understand this system at all.
But it's hard to believe that I would have to have the dealership retrain the system every time I rotate the tires.
One possibility is that the system has to be initially "trained" so that it knows what TPMS sensor ID's are present from the factory. If another sensor is introduced, as in adding a full sized spare, then "training" of the system is again required to make it accept that sensor ID.
I'm going back to the dealer tomorrow and try to get an answer to all this. It's discouraging that the Ford techs don't understand this system at all.
I suspect that is the explanation for what you are observing.
#20
Re: TPMS Problems
If you have a full sized spare with a TPMS I believe thats the issue. From what I understood the system recognizes four tireID's from the four sensors on the wheels. They only transmitt when the wheel is turning I think. In any case when you rotate your 5 tires, ONE of the ID's is booted out of the memory and replaced with your spare.... The system needs to be retrained to recognize the four tires NOW on the axels and you are going to have to retrain the tires every time you rotate that fifth tire in.
I suspect that is the explanation for what you are observing.
I suspect that is the explanation for what you are observing.
So it sounds like I'll be getting the TPMS warning when the spare is rotated in, which would be for 40k miles to go through all four locations. There's got to be a better way.