TPM Question -- got me stumped--

My local dealership is less than knowlegable to put it kindly. I'm having a TPM question that has me stumped.

My TMP light is on and flashing. If I take it to the local tire store they can reset it with their computer (the reset button under dash doesn't seem to do the trick) it works fine untill I take the truck on the highway at about 80 mph it sets the dash off and starts flashing. This seems to be consistant.

What would cause the dash light to start flashing at 80mph that is fine at lower speeds and won't reset? Any suggestions ?

Thanks

 

I don't know too much about the systems (2005's don't have them) but if they go off when the psi is too high in the tire that is likely the cause. You tire pressure can raise as much as 5 psi when driving, especially at high speeds. Maybe you are right at the peak of what your sensors are set for and driving fast raises the pressure just enough to set them off. You could go let like 5-10 psi out of each tire and test it. If that isn't it, I would guess a sensor if faulty.

 

if you have the direct tpm system with the senors mounted on the wheel (aluminum valve stems) make sure to check the spare tire psi too. some older trucks and suv's from toyota had tpms senors on the spare wheels too then they started to go away with it on some. I'd check there first, usually if a sensor is bad or faulty the light stays on solid. and yes over inflated tires can set off the light along with a psi difference as low as 3-5 psi

 

Good suggestions. The 06 models does have the TPM in spare, I checked that. I do have the tires pressure pretty high. I will try letting a little air out. Thanks for the suggestions.

Actually now I think of it don't the TMPs not really care what the tire pressure is (as long as they are all the same) I understand they really don't check the pressure but rather the wheel speed?

I'll Try the tire pressure anyway.

 

You might have to go to a dealership anyways. When the light flashes, it means there is a malfunction and there are probably codes stored. High speed like that usually causes high temps in the tires. You can get TPWS codes for excessive temp that could be caused by a malfunctioning sensor. You also cant just go pressing that button under the dash all the time either.

That button re initializes the system, and if you go pressing it when your tires are all at the set pressure, you are creating a really high threshold. When you set a high threshold, this means the light will come on when the tires lose a few lbs in the cold weather. You are supposed to drop all the tire pressures to about 25 psi, then press and release the button, and then press and hold the button until the tire light flashes 3 times. The tpws ECU will now set a threshold for about 6 lbs lower that what the tires are set at, and after waiting about 5 min, set all your pressures back up to 30-35psi. Include the spare in this.

Now back to your problem. You can try reading the codes and resetting your tpws manually by jumping TC-CG on the DLC3 connector. It should blink out the 2 digit codes with pauses in between like old style check engine lights. I am going to have to post a pic of the connector for you. The thing is if there are codes that require you to replace a sensor, you will need to go to the dealer anyways so they can program the sensor to your truck.

 

The direct system doesn't care about wheel speed, and the light can come on if the pressure is too high.

The indirect system relies on wheel speed.

I also forgot to mention that when you are properly initializing your system, after the 3 blinks, the light will stay on until you get your pressures back up.

 

I'm pretty sure they are set for certain pressures because there are ways to set what that pressure is manually.

 

How do you know if you have the direct or indirect system? was it model year or something else?

Thanks

 

These are all direct. You have direct if you have metal valve stems and a battery in each wheel.

 

You said" It should blink out the 2 digit codes with pauses in between like old style check engine lights" what blinks the tire icon on the dash or something else. Is their a list of error codes somewhere to lookup problem?

THanks for help

ps thanks for the pics

 

TPMS triggers when there is 10psi or more difference between two tires, or if pressure in any tire falls below the set point.

You should adjust your setpoint down to 25psi so you don't have to worry about weather variances.
Air everything down to 25psi, reset the system, then bring everything back up (including the spare) to 32/35/40/45 wherever you like it.

 

Mine is 06 TRD with alum rims I switched to aftermarket rims. But you are saying they are "direct" that read the pressure in the tire not the wheel speed. correct?

 

if you have direct tpms you will have aluminum valve stems not rubber for toyota. indirect you will have all rubber valve stems for toyota. ford used a direct system but their sensors were mounted to a belt wrapped around the inside of the tire attached to the wheel.

 

The local parts guys should check this site ... just saying

 

got you.. I have the direct

 

The tire light blinks. There will be a bunch of lights that blink but you will only be concerned with the tire light. Also, be very careful and make sure you have the correct pins. I'm just trying to help here, but I cant be responsible for what you do.

Honestly, I would try dropping the pressures down if you have them really high and then try the re-initialization process first and foremost.

 

no problem

 

2nd Gen Tacoma are all direct, as are most vehicles now.

Indirect was very common prior to 2006.

 

I will try the pressure first, I appricate your help and expertise as well all the reponses....