Missing Tire Pressure Fob? - Page 2 - Diesel Forum

loft306 · 11-28-2007, 04:55 PM

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: wickedsprint</div><div class="ubbcode-body">I think if you have the fob, you can set whatever setpoint you want. </div></div>unless the proper air pressure is stored in the SJB and has to be manipulated ther via a scanner/programmer.... if so this would highly suck when we change to other than stock tires/sizes, there goes ford over engineering things again.

**PowerStrokeHD** · 11-28-2007, 07:00 PM

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: loft306</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: wickedsprint</div><div class="ubbcode-body">I think if you have the fob, you can set whatever setpoint you want. </div></div>unless the proper air pressure is stored in the SJB and has to be manipulated ther via a scanner/programmer.... if so this would highly suck when we change to other than stock tires/sizes, there goes ford over engineering things again. </div></div>

Has nothing to do with over engineering and more to do with meeting federal requirements on how the system must operate and who has control of what functions. Ford would be setting them selves up for a whole mess of liability problems if they would let the consumer have control over the TPMS low pressure set points.

Ugly-Jeep-Truck · 11-28-2007, 08:41 PM

You're half right, but since it is not even required on our trucks legally, I think they have some flexibility inhow they make it work. It is only required on consumer vehicles that gross in under 10K lbs.

cadamwil · 11-29-2007, 11:28 PM

TPMS tells you which tire is low. This is the reason you need the fob, because after a tire rotation, you need to tell the computer which sensor is at what location. I do not think you can set the warning point. The manual made no mention of setting the warning point.

**manowell** · 11-29-2007, 11:42 PM

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cadamwil</div><div class="ubbcode-body">TPMS tells you which tire is low. This is the reason you need the fob, because after a tire rotation, you need to tell the computer which sensor is at what location. I do not think you can set the warning point. The manual made no mention of setting the warning point. </div></div>

Being that the front and back wheels are kept at different pressures by manufacturer recommendation, I sure hope that you could set the pressures....

cadamwil · 11-30-2007, 01:03 AM

In my truck, the recommended pressure is 65 PSI for all tires. I think the alarm pressure may be low, like 25 psi or so. I will let you guys know tomorrow, I am going to go bug my dealer and show them the problem. I want to deflate two tires, and show them that the computer says they are in a different spot than they are.

**manowell** · 11-30-2007, 10:29 AM

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cadamwil</div><div class="ubbcode-body">In my truck, the recommended pressure is 65 PSI for all tires. I think the alarm pressure may be low, like 25 psi or so. I will let you guys know tomorrow, I am going to go bug my dealer and show them the problem. I want to deflate two tires, and show them that the computer says they are in a different spot than they are. </div></div>

Hmmm. Mine is 55psi front, 70psi rear. Clearly much to learn about this gidget.

cadamwil · 11-30-2007, 04:55 PM

OK, On mine the fob may not be required, I deflated one tire, and it just said "Ding, Low Tire pressure." The turn on pressure for the alarm seemed to be 45 PSI but mine are 65 all the way around. So, the fob may only be required if you have differing pressure recommendations.

mtptuc · 12-01-2007, 04:45 AM

What Cadamwill said

.

That is the party line I'm hearing from my dealer. That is, if your door jamb sticker says 65 all around, you don't get (nor need) the fob. That is the case with my F-250. Still not sure I have a complete understanding here; say I'm towing all the time, and decide I'm a 70 back/55 front guy. Now when I rotate, of course I need to get out the compressor for the new backs, and ease up those fronts. Is this a fobbable event -- as in aren't the sensors gonna be confused after that rotation, or am I looking at this the wrong way? I'm certainly not a fan of driving into the dealer to get them reset.

Bobby Williams, if you're around -- can you give us any insight on how you are handling these TPMS's for your recent deliveries?

slingshot2005 · 12-02-2007, 11:51 PM

I had a set of 35" Pro Comps put on my 08' 350 with 20" wheels. I had to under inflate the tires so that I have even wear across the entire tread. Two days after installing the tires, the low pressure light has shown up. (Why didn't it come on immediately?) I just tried using the fob thingy to re train the sensors. No luck, the light is still on. By the way, I am running 58 lbs. on the fronts and 62 on the rears.

**PowerStrokeHD** · 12-03-2007, 12:00 AM

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: slingshot2005</div><div class="ubbcode-body">I had a set of 35" Pro Comps put on my 08' 350 with 20" wheels. I had to under inflate the tires so that I have even wear across the entire tread. Two days after installing the tires, the low pressure light has shown up. (Why didn't it come on immediately?) I just tried using the fob thingy to re train the sensors. No luck, the light is still on. By the way, I am running 58 lbs. on the fronts and 62 on the rears. </div></div>

Using the fob to retrain your sensors will not cure your problem. The only thing that will turn off the light is airing up the tires beyond the sensor low set point. Unfortunately your 35" tires will be over-inflated before you reach that point.

From the B pillar, what pressures are supposed to be in your factory tires? My guess is the light is on due to the TPMS thinking the rears are low.