all of a sudden my tire low pressure light came flashing on- and reads "service TPM". I went to dealer today- said it was fixed- 20 mi. later-lights came on again I have checked all of the tires & spare for pressure -all are right on - has anyone had this problem-if so, whats going on? thanks for your help in advance

 

Stupid government regulaton after the Ford Explorer / Firestone debacle for people too lazy to check their tires... Mine randomly comes on and seems to be linked to GPS because everytime I get near the dealership it goes off! I keep up with my pressures and check my tires at each fill-up so ... I just ignore it.

The dealer did replace a sensor under warranty a few months ago but hear they are expensive if you are out of warranty.

 

Johnnie,
This should be a quick fix. First check the pressure in all your tires again making sure you've got 35-40 psi in each. Try performing the TPM Learn Mode procedure as outlined in your manual, this takes less than 5 min and should correct the light by reseting the TPM.
4 steps (1.) parking brake on turn ignition on with engine off. (2.) turn exterior lamp **** from auto to on 4 times in 3 sec (double horn chirp sounds) (3.) ft left tire release air for 10sec stop listen for horn chirp in about another 10-15 sec. then repeat clockwise to each tire RF, RR, LR. (4.) turn ignition off to lock and you've finished Learn Mode.

Simple as that Johnnie, don't forget to check tire pressure again. Now maybe the dealer didn't do this or just maybe a sensor is defective but probably not. Repeat it if the light comes back on or if you ever rotate or use the spare. I'd do this before getting into a deeper analysis.

 

This may be a stupis question but should the spare on the back be checked as well? Or only when it's being used?

 

No Fancy, the spare is not part of the TPM learn mode procedure. Additionally I might also include here, I came to the conclusion after reading some posts by some fine senior members on this here forum that the onboard computer only picks up readings from the 4 tires TPMs on the road and not the spare. I also read that in mid year production 07 the sensors were not placed in spares for cost savings. I know this can be a bit confusing, (why wouldn't it pickup the spare TPM too?) but I'm just repeating what conclusions I came to. Perhaps others more knowledgeable will care to comment but just wanted to pass this reply on quickly. Interesting the things you learn here even dealers are not aware of so hey, don't be afraid of what might seem stupid questions, I have many. Ha!

 

One last post to clarify some of my statements to Fancy then I'll shut up. If you have sensors on all tires on the vehicle including the spare you can still rotate the four tires on the ground without reprograming the BCM. However if you rotate in the spare you need to do the reprogram with the TPM Learn Mode procedure. If not, it will continue to read the new spare and not the old spare now on the ground.
I found this out by putting a flat tire I had on the back of my '06 H3 for a few weeks without reprograming the BCM. The BCM was still reading my unfixed flat thus sending out a TPM alert.
Be alert to this when fixing flats or when the local shop rotates your tires, etc. Find out if your spare has a TPM sensor.

The point is the BCM can only recognize 4 sensors at a time even though it reads every sensor close to it including the neighbors if parked close.

 

no kidding, wow. Glad I asked. I'd like to just bypass the damn thing as I check my tires all the time. haha. Thanks for all the info. guys!!