TPMS and the fury it releases on the dash and DIC

[MarkT]

44 isn't bad. It rides smoother then my Lightning ever did. No they can't reprogramed you would have to mess with the wheel speed sensor and abs sensor also. The second gen TPMS is such a PITA. I don't get a light until it drops at least 12 lbs below whats on the door. So 35 won't trigger a light.

Hey Tank... Can you elaborate on how the Raptor TPMS is tied into the ABS and or wheel speed sensors (and aren't the ABS and wheel speed sensors the same thing?)

thanks.

 

[The Tank]

Now that you mention it I remember Big J saying he got an ABS light when he took out his wheel speed sensor. But basically the brick in your wheel or band on the wheel I haven't looked to see which we have. Is reference point I don't want to use timing marks as an example because it's not a good one but basically the truck knows how fast in RPMs the TPMS sensor is supposed to spin at a given speed for air pressure X and its measured and the info is transmitted by the wheel speed sensor, abs sensor or as Ford calls it now vehicle speed sensor.

 

[Nv Guy]

Now that you mention it I remember Big J saying he got an ABS light when he took out his wheel speed sensor. But basically the brick in your wheel or band on the wheel I haven't looked to see which we have. Is reference point I don't want to use timing marks as an example because it's not a good one but basically the truck knows how fast in RPMs the TPMS sensor is supposed to spin at a given speed for air pressure X and its measured and the info is transmitted by the wheel speed sensor, abs sensor or as Ford calls it now vehicle speed sensor.

Hmm, my warning light wouldnt go off untill I got to 44 PSI & that was while sitting in the garage.

 

[MarkT]

Now that you mention it I remember Big J saying he got an ABS light when he took out his wheel speed sensor. But basically the brick in your wheel or band on the wheel I haven't looked to see which we have. Is reference point I don't want to use timing marks as an example because it's not a good one but basically the truck knows how fast in RPMs the TPMS sensor is supposed to spin at a given speed for air pressure X and its measured and the info is transmitted by the wheel speed sensor, abs sensor or as Ford calls it now vehicle speed sensor.

I see where you are coming from... What you seem to be describing is a "passive TPMS" system where the computer uses wheel speed to "calculate" if there is a low tire.

But I'm 100% sure the Raptor uses a "direct TPMS" system that is not tied into the wheel speed sensors. In other words, the valve-stem mounted sensor in the Raptor tire measures the tire pressure directly and transmits the pressure information via radio waves to the receiver located in the Smart Junction Box.

 

[The Tank]

I see where you are coming from... What you seem to be describing is a "passive TPMS" system where the computer uses wheel speed to "calculate" if there is a low tire.

But I'm 100% sure the Raptor uses a "direct TPMS" system that is not tied into the wheel speed sensors. In other words, the valve-stem mounted sensor in the Raptor tire measures the tire pressure directly and transmits the pressure information via radio waves to the receiver located in the Smart Junction Box.

I'll have to check the owners manual but I think it gives a percentage not a number of pounds down to cause the light. If its direct I would assume that it would state that X pounds low will cause a light but Idk.

 

[MarkT]

I'll have to check the owners manual but I think it gives a percentage not a number of pounds down to cause the light. If its direct I would assume that it would state that X pounds low will cause a light but Idk.

I don't remember what the owner's manual says... but the "TPMS law" is written in percentage so my bet is the owner's manual would follow that convention.

(I think the law says the warning must come on when a tire is underinflated 25% or more so that's probably what the manual would say.)

 

[The Tank]

I don't remember what the owner's manual says... but the "TPMS law" is written in percentage so my bet is the owner's manual would follow that convention.

(I think the law says the warning must come on when a tire is underinflated 25% or more so that's probably what the manual would say.)

Ok, that makes sense.