Low tire indicator

my wife's 07 Santa Fe just had the low pressure indicator come on for the
right rear tire. Checked pressure and its same as front. Even added a
pound of air to all tires but still showing low pressure.

Thought it might be because last night temp got down to 55, but drove car at
least 15 miles and still the indicator is lit.

Is there anything I can reset so I don't have to drive 60 miles to the
dealership?

Thanks,

Jim

 

What does the manual say? Did you go through more than one ignition cycle?

HMA Service does not show a particular reset that I can see, but reading
this indicates reset should be automatic.



General Description
The TPMS display device is located on the instrument cluster to provide
information about TPMS operating conditions and tire pressure. The TPMS
display device is consist of TREAD indicator lamp, Location lamp and TPMS
Warning indicator lamp. The TREAD indicator lamp is turned on when pressure
of one or more tires are below the warning limit level. And then, the
location lamp displays the tire position that is the pressure below the
warning limit level. The TPMS Warning indicator lamp is turned on if there
is the failure in the system.

Troubleshooting:
a.. Information to ascertain (TREAD Lamp) :

Was puncture repair fluid used (it should not be)?
- This can cause the sensor pressure port to block and incorrect warning
to occur.
What temperature were tires last inflated at?
At what temperature did warnings occur?
- Pressure change is approx. 1.5psi / 10 C increase.
Have the tires been checked / inflated since the lamp first came on?
b.. If the TREAD Lamp is on :

Check for short circuits.
Enter Diagnostics and read TREAD Warnings Local Identifier Data.
Check to see if warning type is under inflation or leak.
If the warning is for under inflation, then:
a. Re-inflate the wheel with the matching sensor ID to it's desired
Placard pressure.
b. Check to make sure that the TREAD lamp turns off (this may take up to 1
minutes if the tire is not rapidly re-inflated).
a. If the warning is for a leak, then:
b. Fix any puncture and re-inflate the tire to the desired Placard
pressure.
Wait up to 1 minutes and make sure that the TREAD lamp turns off and the
lamp does not turn on again.
c. If lamp comes on again:
d. Re-check pressure for signs of a puncture and Re-Check TREAD Warnings
Local Identifier Data.
c.. If the Placard pressure is OK and the TREAD lamp still does not turn
off :

Turn wheel a quarter turn and again wait 1 minutes (the sensor may be in
an RF null).
If the lamp still does not turn off :
check for loose receiver wiring and replace the receiver with a known good
one if necessary (follow configuration & learning procedure).
- If the problem still exists, replace sensor.
- Ensure that all tires are inflated to their correct Placard pressures.
- Clear TREAD warnings.
- Test drive the vehicle and ensure that the TREAD lamp does not come back
on.

 

Manual insinuates that the tire must be low. That is all. So evidently,
there is something wrong with the information transmitter which it says is
mounted in the tire behind the valve.

Vehicle has been thru multiple ignition cycles since it first came on. And,
several more since I upped the inflation in the tires.

Guess there is no way to avoid going to the dealership.

Thanks for the information.

Jim

 

Just returned from store. Light was on when going there, but was off when I
returned. Noted that the outside temp was now 75 degrees, so perhaps it is
the cold. Will see again next month when temp will probably get down to
lower 50's.

Jim

 

Temperature certainly affects pressure, but if affects all tires the same.
Could be one sensor is temperature sensitive. If it continues to happen the
same way, I'd take it back to the dealer. We may not see 50 for an other
month either, but we are on the low end of it

 

And that sir, is precisely why I don't like all of the features being
incorporated into cars today. Many are indeed useful, but sometimes they
are simply problems looking to surface, which really address no real
shortcoming in the real world. For those who "need" tire pressure monitors,
then they can deal with the issues, whereas a simple look could have been
equally or more informative. But - gadgets do attract us sometimes, and
this is one of them. Now... on to a discussion about those ridiculous back
up cameras...

 

The low temperature certainly could be the issue, as mentioned in a Hyundai
TSB. What's the pressure in the tires, and what's recommended on the
placard on the driver's door pillar?

 

Good question, I see I didn't put down the reading. It was 26.5 in both
front and back on passenger side (back tire was what was getting the low
indication). Driver's side had 27 lbs. Certainly doesn't seem low do you
think?

Thanks for the reply.

Jim

 

Yes that does seem low. What does the placard say on the driver's door for
tire pressure?

 

I have 4 tire guages, some of them show that my 06 sonata w/17's have 20
lbs, others show 25 or 30, anyone know where to buy an accurate tire
guage???? Sidewall says 41 PSI. I filled them to 40, then went to
Discount Tire for rotation and (where they say they check pressure) when I
checked again they were back to 22...NEED a good guage!

 

Sounds low to me as well. The lamp is to come on when the tire is 20% or
so low. I'd recommend 35PSI in this vehicle, but suspect the placard may
say 33 or so. That brings us back to the question: What does the placard
say?

 

Any autoparts store will sell a decent tire pressure gauge. Generally, if
you're getting sporadic readings it's because you're not holding the gauge
down fully on the valve step when you take the reading. Make sure if you
use a stick type that you push the stick back in after each attempt to read
pressure.

That marking on the sidewall of your tire is the max tire pressure. It is
not the recommended tire pressure. 40psi is high for a car like that.
Likely it should be between 30 and 35psi.

 

Placard says 30 PSI. I put 32 in wifes 07 Santy. Then checked my 07 Santy,
which hasn't been in for a service yet, and the tires were setting dead on
at 30 PSI. Upped mine to 32 also.

Placard saying 30 PSI and the tire with the indicator being 26 1/2, that is
just over 10 %. Probably be a good thing to mention it to the service
manager next time I'm there, don't you think?

Thanks for all the responses to my concern.

Jim

 

I bought one of those digital guages from Sears several years back. Since
then I've purchased the Black and Decker Air Station cause I have Bikes,
Cars, and a golf cart to keep tires pumped up on. Both guages are dead on
to each other. Doesn't mean they are right but two outta two ain't bad.

I like the B&D Air Station cause you set what pressure you want and it will
automatically shut off there, and moving on to the next tire, just have to
turn switch off and then on. Pressure is equal on all tires.

(No I have no stock in B&D, nor do I work for them).

Jim

 

Ditto what Mike M. says. Additionally:

At one time I had about 10 of those "stick" gauges. They did not
agree. The round dial type also seemed off.

I ordered a digital gauge from JC Whitney. I've had it 12 years
and never even changed the battery. I have another digital I
picked up at a garage sale and I use that also.

Sweetie got a new car and I bought her a digital gauge from
Harbor Freight for less than $10.00. It was nicer than the two I
have, and... all three agreed. I will buy this one for myself
when I get a chance.

I threw all the crap gauges in the scrap bin and never looked back.

Some wise person pointed out to me that most store/station tire
gauge/chuck devices spend their days getting dropped on the
ground, and were not to be trusted. 10 years of bringing my own
gauge has showed me this is, indeed, true.

Tires: your life is riding on them.

PB

 

Whether it's 10% depends on how the sensor measures pressure. If it's
measuring relative pressure to the atmosphere (the same thing you measure
with your gauge), then I agree it's about 10%. If it's measuring actual
pressure, then it's more like 20%.

 

thanks for all the input...When I get back home to CA, on to Harbor Freight
it is!!

 

HT,

Have you looked at the tpms units on the Sonatas for 08 (and most others I
assume)? It appears to me that they have a lithium cell (CR2032) and I asked
the service department on the servicing of these things. I guess I wait
until the TPMS light comes on? One of the techs suggested I go to nitorgen
(don't shoot me, just stating facts!) as an alternative to keep these things
rust/corrosion free. Why not use the ABS signal as an indicator? The
circumfrence of a tire changes a with it's pressure, right?

 

I've only had a couple off and haven't paid much attention. I don't think
the battery is replaceable. If you have a system which tells you which
tire is low (not sure which cars have which system), there is a
transmitter in the fender well which sends a radio signal to turn on the
TPMS sensor. I.e., it's off when needed, saving on battery life.

GM actually used a system which used the wheel speed. It proved
troublesome. Rotating the tires would cause the tire pressure lamp to
illuminate a few miles down the road.

 

But, at least on my GM model, you can just press the reset button so it can
adjust itself to the new position/condition.