I put my new wheels and tires on today, and I didn't teach the new sensors yet. (I will tomorrow) On the test drive it just didn't update, I figured it would update and read zero and put the warning light on, but nothing.
Is this normal?

Thanks,

DJ

 

IIRC, it takes a while for the system to understand that it's getting absolutely no sensor information. The time it takes for the warning to appear has changed over the years, for your 2008 I think it will be 20 or 30 minutes after you start the engine.

The real experts will be along soon.

 

I only took it out for about ten minutes, I just ask because my original sensors would actually update within two blocks of driving.

 

Jim had some expert advice for you!!

I agree with his 20 to 30 minute time period.

If you had left say, your original 2 wheels/tires/sensors on the front, and put new wheels/tires/sensors on the rear without doing any sensor programming, within a minute or two of starting to drive your TPMS would get signals from the front sensors but nothing from the rear ones (because they aren't programmed in, and the TPMS just doesn't recognize them). In that case you would get DIC messages about the rear wheel sensors/tire pressures (xx psi) almost immediately after beginning to drive.

The car knows the TPMS is working because signals from 2 of the sensors are being received and processed, but when it doesn't hear from the other 2 sensors the TPMS knows the tire pressure sensors are the problem.

In your case, you changed all 4 wheels/tires/sensors without doing any programming. When you start to drive, the TPMS is expecting to get signals from the sensors. When it receives NO SIGNALS at all from any of the 4 sensors, the TPMS isn't quite sure what the problem is.

What's the chance that all 4 sensors would fail? They would probably fail one at a time over a period of time such that each one would either be replaced individually, or all 4 would be replaced with all new ones. At any rate, all 4 should not be inop at the same time.

Or, nobody would drive without sensors - right??? The runflat tires require tire sensors because they don't give the handling feedback you get when a normal tire goes flat.

When the TPMS gets NO SIGNALS at all from any of the sensors, it starts to think that the problem may be with the TPMS computer in the car (actually part of the RCDLR module).

Butt....it takes a while for the system to really decide that the problem really must be the TPMS. In the 2005/2006 it was about 60 minutes. In the 2007 and I think 2008 it was around 30 minutes. Those times are in the 2005, 2006, and 2007 Owner's Manuals. They have left times out of the manuals from 2008 on, but my 2009 (and I suspect all model years since then) are 20 minutes.

After that period of time the system says "okay - no signal, and nobody would run with no sensors, so the problem must be the TPMS!!"

After the time period running with no sensors is up, you'll get the "Service Tire Monitor" message - meaning the car thinks you must have a TPMS problem.

So....your situation was normal. If you had driven for 20 or 30 minutes you would have seen the DIC message.

Program your new sensor ID#'s into the TPMS and you won't have any problems.

I assume you got the correct sensors for your model year. The 2005-2009 uses one part#, and the 2010 and newer uses a different sensor. They are not compatible with each other, so you must have the correct ones for your model year to be able to program them into the TPMS computer memory.

Let us know how it goes after programming them!!

Bob

 

Bob, you are correct about the 30 minute delay before the DIC message pops up on the '08 model and the pressures will show as XX. If it picks up a signal from your old sensors that may be nearby (in the garage, etc) it'll display whatever they transmit until you leave that location for another 30 minutes. Of course, if the old sensors are not in inflated tires, the reading will be 0 and a DIC message "FLAT TIRE".

Contrary to popular belief, you are not speed limited without sensors.

 

I did have my old wheels in the garage before pulling out, so those readings stayed. I programmed the new sensors today which seemed to go ok. I haven't driven it yet because I am in the process of waxing her.
Thanks for the replies!

DJ

 

When the old wheels and sensors are in the garage near the car, it is possible to have everything appear normal for a long time. We have seen a number of people on the forum who were in this situation and said that the sensors must have programmed themselves, because everything was working fine. If the car is only taken out for short drives, the whole situation could appear normal for quite a while....until a flat tire ruins the whole situation.

 

Just to do a check, drop the pressure in the old wheels to 20 psi. If your car has 30 psi, it'll be easy to spot which ones are talking to the car.

 

Drove the car today, everything works just fine. Actually these sensors read exactly what my tire pressure gauge does, the original ones always read at least 2psi lower.

DJ