Triangle light with low tire pressure
11-15-13, 05:02 AM
#1
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Triangle light with low tire pressure
Greetings all. As I'm currently looking for another LS, I noticed this in an ad photo and was wondering if the triangle should be lit when the low tire indicator comes on or could this mean something else? Let me know. Thanks.
11-15-13, 06:48 AM
#2
I'm pretty sure the triangle just comes on when the tire has low pressure or if you have air suspension and you have the height set on "High". I used to get the triangle all the time because one of my tires kept leaking air. There is a button under the dash above the gas pedal that will reset that light. It's really hard to find that button though.
11-15-13, 07:38 AM
#6
Prochamber - According to the Owner's Manual (p. 83 for 2005), the triangle warning light means "check the multi-information display". It is analogous to the "master caution" in an airplane.
Ultim8mind - Are the sensors you mentioned the wheel speed sensors (which are not in the wheels or tires) ?
The LS430 "low tire pressure" system depends on differential wheel rotation speed, not on a pressure sensor.
That's why you have to reset it when the tire is inflated - so it has a reference value for the tire circumference.
Ultim8mind - Are the sensors you mentioned the wheel speed sensors (which are not in the wheels or tires) ?
The LS430 "low tire pressure" system depends on differential wheel rotation speed, not on a pressure sensor.
That's why you have to reset it when the tire is inflated - so it has a reference value for the tire circumference.
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11-15-13, 01:13 PM
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good lord. would someone please have an accurate explanation before posting?
these cars do not have any pressure sensors in the wheels. the principal they operate under compares the axle positions during rotation. if one axle rotates faster than the other (because the circumference of the tire is smaller) it is assumed that the pressure in a tire is falling.
you can do two things: 1. reset the idiot light 2. reset the TPMS system and see if the fault returns.
both procedure are simple and detailed in the manuals.
if you pay someone for new sensors in the wheels, you don't get what you paid for b/c there is nowhere to install them!
these cars do not have any pressure sensors in the wheels. the principal they operate under compares the axle positions during rotation. if one axle rotates faster than the other (because the circumference of the tire is smaller) it is assumed that the pressure in a tire is falling.
you can do two things: 1. reset the idiot light 2. reset the TPMS system and see if the fault returns.
both procedure are simple and detailed in the manuals.
if you pay someone for new sensors in the wheels, you don't get what you paid for b/c there is nowhere to install them!
11-15-13, 05:03 PM
#10
jmscott - My understanding is that the TPMS system compares the current tire circumference with the reference circumference (which is measured when the reset button is held down), rather than the difference between pairs of wheels. Do you have a reference for the design of the system?
Thanks much,
Gene
Thanks much,
Gene
11-15-13, 06:03 PM
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jmscott - My understanding is that the TPMS system compares the current tire circumference with the reference circumference (which is measured when the reset button is held down), rather than the difference between pairs of wheels. Do you have a reference for the design of the system?
Thanks much,
Gene
Thanks much,
Gene
My understanding is that the rotation is compared with the reference, yes. However, the reference is set when the entire TPMS system is reset, not just the button pushed to reset the light. If you reset the light and there is a circumference differential (high or low) the warning light will just trip again a few minutes later.
11-15-13, 11:07 PM
#12
Yes there is a spot, atleast on my wheels for a TPMS sensor, but what do I know? I mean I just know they sell them to install in your wheels, they can be tricked but putting them in a piece of PVC even, and different kinds of things. I was simply assisting someone who asked a question, to the best of my ability because I did not bring my manuals with me on this deployment to Afghanistan, so I was speaking from my previous first hand knowledge on the subject.
11-16-13, 04:04 AM
#13
I'm sure the system is monitoring based on rotation of tire relative to each other using the abs sensors and not each tire individually to the "baseline." I say this because I had a case when I first got the LS and the tire pressure was fine. Then without checking for a few months, all four actually dropped to 24 lbs and no warning. I thought the system was bad. I read on the forum that it operated based on abs rotation and so I lowered the pressure of just one tire to check and it triggered the warning. I believe the reset is just to get a base idea of what the current rotations will be.
11-16-13, 07:54 AM
#14
jmscott - Yes, the "system reset" is when the reference circumference is calculated, not just the warning light reset.
AlexusAnja - the problem with that design is that there are situations where the tires will indicate different rotational speeds (but should not activate a warning).
Examples:
1. Replace only one tire with a new one when its twin (on the opposite side of the same "axle" has significant wear.
2. Turning (where the outboard wheels must rotate faster than the inboard ones), although perhaps a minimum time limit could help prevent false alarms.
AlexusAnja - the problem with that design is that there are situations where the tires will indicate different rotational speeds (but should not activate a warning).
Examples:
1. Replace only one tire with a new one when its twin (on the opposite side of the same "axle" has significant wear.
2. Turning (where the outboard wheels must rotate faster than the inboard ones), although perhaps a minimum time limit could help prevent false alarms.
11-16-13, 08:31 AM
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I had the chance to review the instructions in the online manual and it also states after you reset the switch to drive the car for more than 1 hour or 19 mph or over. Later!