On my way in to work this morning my TPMS light started flashing, I thought I must have a tire that was real low so I jumped over onto the shoulder & checked it out, all tires were good, by the time I got back into the truck, it had stopped flashing, then went off as I got about another mile down the road. About another 30 miles later as I am almost to work (I commute 60 miles each way) it starts blinking again, same thing, blinked for a few minutes, then went to just on, a few minutes later it went off again. Any idea what might be going on?

 

Here is a thread with an outline of the Ford TPMS system:
https://www.ranger-forums.com/wheels...-system-52133/

The TPMS system isn't active until you reach 20mph and only checks pressure every 60seconds so delays are part of the system parameters.

If you have actually tested the pressure in each tire, and still get a light now and then, I would suspect a sensor in a tire is going bad, they do run off a small battery which at some point is too weak to transmit reliably.

I believe a $50 "reset" tool is needed to recalibrate the system, and that may not fix the problem.
Ford part number 8C2Z-1A203-A

The '08 F-150's came with the reset tool, manual even lists it as included in the reset proceedure

 

Its pretty much an idiot light they don't serve any real valuable service and they are way to finicky. Most have a service life of about 5 years and there about $100 a piece because you can't replace the battery you have to buy the whole sensor so i wouldn't sweat it to much. Also they do make a reset tool but that is usually only for certain vehicles that have the receiver mounted inside the tire well so when you rotate they have to "relearn" the sensors location. Also the spare may or may not have a sensor so check that one to, and the flashing of the dash light may be a code count the flashes and the google TPMS code "whatever it is" and see what it stands for. This system is another one of those sounds useful on paper but really doesn't work in the real world lol

 

It didn't do it again at lunch, on my way home or on the way here this morning, so maybe it was just a freak deal?

 

Cold affects them to on cold mornings they can go off for no reason especially if the batteries are starting to go.

 

I don't know how its works but I'm sure there is a battery involved, my father in law had an 06 Kia Optima that had one, they called "weak signal" and wanted $79.00 to replace it. I guess they would all go eventually.

 

yeah ford uses band sensors and kia uses stem mounts the band has to usually be replaced with the sensor because they are universal and cut to fit when installed which means they usually stretch when you take them off. Thats why they are a little more expensive.

 

Yep, I wanted a full size spare after I bought the truck but they wanted 70 for the bad and 45 for the sensor... I guess its not whats on the car that makes it safe jist the cost of it makes it safe!!!

 

Yeah kinda like the donut spares on all cars now to force you to repair your tire id love to see someone with a 350 towing a trailer and have to use a donut because they got a flat. But back to the TPMS i know people that ignore CELS why would they pay attention to any other light lol. Any vehicle as only as safe as the driver/mechanic in my opinion.

 

Been about 3 weeks, hasn't done it again.

 

Most likely a temp thing heating and cooling causing changes in pressure i wouldn't worry to much. People drove cars for decades before TPMS came around. lol

 

Anybody know how to disable the thing? I made the mistake of changing wheels without keeping the sensors and the light drives me insane....

 

Its programmed so you can't. Id imagine the easiest way is to remove the bulb.

 

Just a couple of screws hold the clear dash panel on. Take it off & put a piece of black tape on it.

 

Good point... kinda like the flashing '12:00" on the VCR...

 

You still have a VCR? haven't seen one of those in years. lol

 

I haven't seen one in years either, but the last time I did it had the "black tape mod" on it...