Hey guys - Check out these two photos:








A low pressure warning is always shown regardless of indicated pressure. (And I have verified the actual pressures with a digital gauge). And the TIRE idiot light is always on.

Any insight from y'all is much appreciated!

2016 Z51 LT2 6,300 mi.

 

Congratulations, that is one I have never seen before... Dealer may have to reprogram the monitoring system.

Have you tried to read the actual sensor output with a handheld tool?
It may be sending a different pressure than is showing up on the dash display.

 

Yep congrats . . . new one on me too, but possibly a failing TPMS sensor.

 

Thanks Tex and Foosh - I don't have the tool to read the transmitter. The cotton pickin' display shows the correct pressure though, so that part seems OK!

I did just complete the mag ride upgrade. But, so far as I am aware, that's a completely separate controller...

 

MSRC is a totally different control module.

The TPMS sensor may be reading the pressure correctly, but triggering a false warning, or conversely, that channel in the TPMS module may be falsely registering a warning. It could be as simple as reflashing the TPMS module or replacing the sensor.

 

Thanks, Foosh - I'll give that a go.

 

Does it continue to show the problem once you drive the car for a few minutes? Could be that the small battery in the left rear tire sensor is failing and not hold a charge very well. Driving will recharge the battery (takes a few minute to raise it just up some).

 

Sounds like a bad TPMS. To verify I would rotate the rear tires as the issue should move with the defective TPMS. No need to register the tires like you had to on the C6 as the C7 TPMS self register. Just rotate the tires and then drive for ~4-5 mile and they will self register.

 

^

Good idea. Try that first, and if the warning moves to the other side, you'll know exactly what is going on. If it doesn't, it's in the module.

 

And more strangeness - it's not always the same tire! Sometimes it moves around, and can show multiple tires at the same time. At times the low pressure indication on the display will be on a tire that's reading a pound or two higher than the rest!

Also, the idiot light is steady on. I thought a flashing light was supposed to indicate a transmitter failure. And why in blazes would the tire transmitters send both measured pressure and a fault? I'd have put that function in the dash display controller!

 

Yes it does. Stayed weird for six hours on a recent road trip, and also after several low speed trips around the block after finely adjusting the tire pressures.

 

OK, thats got to be a TPMS module issue, which interfaces w/ the Body Control Module (BCM). As long as you can duplicate the problem at the dealership, they should be able to run it down quickly.

 

Thanks, Foosh. They'll see it on Monday.

 

I had the same issue with my Z, however, I did 2 things to fix the issue. First I disconnected the negative battery terminal for about a hour. Next, I pulled up the tire pressure on the DIC, I held the center button on right steering wheel, the car went into TPMS learning mode, drove car, it learned the sensors, problem went away. Might be something to try. The cars computers just get fussy sometimes & need a reboot.

 

Thanks! Worth a try and saves a trip to the shop. I'll let you all know.

Anyone else seen this?

 

It does sound like the TPMS module has an issue.

I am not sure how the TPMS system responds to interference but thanks to the global market all of our car systems (RKE, TPMS, etc.) plus things like garage door openers are moving to 433 Mhz. which is acceptable for all major markets. Last Spring I was doing the biannual switch between winter and summer tires for my Cadillac ATS and my 2014 requires using a TPMS learning tool held near each tire sensor to pair them when wheels are rotated or changed. It is a simple process that involves putting the car into TPMS learning mode and then walking clockwise around the car and activating the learning tool at each wheel and takes less than 30 seconds. In Spring two tires wouldn't pair at all and the other two were stubborn. The only difference from the past was I had installed a new garage door opener for that stall that is on the same frequency as the TPMS sensors and apparently activating the TPMS tool also caused the opener to try to query a remote resulting in its signal interfering with the obviously weak signals from the TPMS units. I had to move the car a couple hundred feet down the driveway and then it paired instantly like it always had in the past. Since I ran into this issue I have read of several others running into the same problem. Our FCC and similar agencies around the world used to be run by engineers who understand physics instead of lawyers who largely don't and the results show

 

So - an update for those interested:

Dealer tried resetting the TPMS without success, (as anticipated). They have to get their C7 guru on the job. They've likely never reflashed a TPMS module before.

I'll keep y'all posted. And thanks again for all your input.

 

A main car battery on the way out, or interference of some sort can cause that kind of problem also.

We had a club member whose C6 had intermittent TPMS problems, the dealer kept throwing parts at it but the problem persisted.

One day the Tech unplugged the phone charger that the owner kept in the car, the TPMS problems disappeared immediately and never came back.
I tried a Valentine Savvy unit plugged into our OBD port , to power the detector and allow speed muting. It caused our tire temperatures to show Warm even when they were down to 19'f.

 

You can deactivate the TPMS all together to see what happens. In park with the car running, set the parking brake, then hit the traction control button 6 times in 5 seconds. Drive around for a bit and then stop and **** the car off. When you turn it back on the TPMS will be back on. Worth a shot.

 

Dealer fixed the issue. The ticket says, (complete with misspellings, etc), 8020010 ELECTRONIC SUSPENSION CONTROL MODULE REPLACEMENT 1857 W
6939 MODULE DID NOT RECOGNIZE TPMS CONFIGURATION 8020010
PARCEL TIME RESET TPMS SETTINGS

So, I'm guessing here that the Mag Ride upgrade they did caused the problem, assuming that the MRCM is the same as the ESCM. We'll likely see more of this as more mag ride upgrades are done.