ford4v429

anyone know if you get a TPMS failure, how to tell which one is causing it? the wifes car has it, been driven plenty far enough to reset, but its not...we got it used, wondering if someone mighta swapped wheels or something...hate to break down all 4 tires to find out.

bob

The dealer should have a TPMS tool, or possibly an independant tire dealer, thats aboutt he only way I know to find it, there might(?????) be a diagnositic function with the OBD system that uses the transmitter ID, this last part is pure speculation though (some TPMS systems log the transmitter ID)

EastCoast07GtCs

I can tell you from experience that mine went off a while back. I tried everything, filled them up to proper pressure, ran them a few miles in case they were dormant, but nothing worked. Finally bit the bullet and took it to the dealer. Told me they had to re-flash the ECM. No indication why it happened, basically saying they had no idea.

boss429man

Some have them in the spare so make sure the spare is full.

viiStang

Hey all.

Question, was on my way to work this morning and my Low Tire Pressure warning came on for the first time in 11th months I've owned this car. On the way home the alert was still on. When I got home I checked the tire pressure on all 4 tires and they were between 28 and 29 psi. It think it's strange how they are all 4 at the same psi under what it's saying it should be. Checked the door sticker and it looks like they need to be at 32 psi.

Does anyone know how low the psi needs to be before the alert goes off? I guess when it drops under 29?

denlem

Mine went off a few weeks ago and the tire was at 24 when I checked. Filled it, about 4 days later it went off again. Tire was at 24 again. Keep saying i'm gonna get the tire looked at but it hasn't gone off since. Haven't checked it either.

Suntzu

I think the manual said 20% less then recommended pressure will activate the light. I have seen others post that wheels out of balance will also trigger the warning. On your issue, if you checked your tires AFTER a commute, and assuming you do decent speed, enough to heat up tires a little, then your 28-29 psi all round would be a warm reading with the cold reading being a few pounds fewer. Just a guess though.

viiStang

Not much of a tire expert. So to get an accurate reading I should measure them again in the morning you're saying?

I'm thinking of just filling them to 32 psi tomorrow...

Suntzu

yeahs sounds good, if that is what the plate on your drivers door says (assuming stock size tires)

viiStang

Right my bad. I have the stock 18" fanblades.

bob

Checking them cold? Yup, thats the best time (even better if you've got a digital guage). Scribble down the pressure for each wheel and then go fill them based on the deviation from the factory (Ford) reccomended air pressure, that way the increased pressure due to heat will be accounted for.

viiStang

Yeah I measured them this morning. Now they ranged from 25-26 psi cold. I filled them up to about 33-35 psi at the gas station this morning to account for heat and my alert is now gone.


Thanks all!

ford4v429

little update:
bought one of the little remote fob/calibration thingys off ebay, only took a minute to verify the only one not working was the right front(horn wouldnt chirp when checking that tire). wasnt sure if one failed if rest of sequence would work, but apparently it does(might confuse it as to what wheel is where if 'out of sequence', but at least it pointed out the dud) as checking any tire at any time during the relearn procedure would chirp the horn except the dead one.

Mark S.

Just another great gadget that will go wrong and cause numerous visits to the dealership...you have to hand it to them, they know how to get you back to the dealership.