To help keep drivers aware of impending flat tires, tires that will prematurely wear because they are too low, or even tires that are too highly pressurized, the Equinox EV comes with a TPMS that can warn drivers or inform them in real time of each tire's pressure.
DIC, App Tire Pressure Display
The tire pressure readings can display in the Drivers Info Center (DIC)—OM p 108 —and also in the myChevroltte app. I like to have the tire display up all the time to catch a leaking tire before the alert goes off but day-to-day to maintain the correct tire pressure: 42 psi (OM p.295). If I see a drop a few psi I top it off. If it happens regularly, there may be a slow leak in the tire bead or even a nail in the tread.
If the tire is overinflated by more than 35 kPa (5 psi), the horn will sound multiple times and the turn signal lamp will continue to flash for several seconds after filling stops. To release and correct the pressure, while the turn signal lamp is still flashing, briefly press the center of the valve stem. When the recommended pressure is reached, the horn sounds once. OM p.298
Sensor Accuracy
In my experience it's not unusual to see a TPMS disagree with a manual gauge by a few psi. Of course then you get into the accuracy of the hand gauge as well. Maybe it's off a few psi.
You can compare the car's reading with a number of tire pressure gauges to see if there's a consensus of some sort. Or, you adjust and mentally add a few psi to what the TPMS displays. I'd like dead nuts accuracy, but the most important function is to alert on a big pressure drop indicating a severe puncture.
TPMS Sensor Matching Process — Auto Learn Function
Each TPMS sensor has a unique identification code. The identification code needs to be matched to a new tire/wheel position after rotating the tires or replacing one or more of the TPMS sensors. When a tire is installed, the vehicle must be stationary for about 20 minutes before the system recalculates. The following relearn process takes up to 10 minutes, driving at a minimum speed of 20 km/h (12 mph). A dash (-) or pressure value will display in the DIC. See Driver Information Center (DIC) > 108. A warning message displays in the DIC if a problem occurs during the relearn process. OM p.298
TPMS Sensor Matching Process — Manual Learn Function
Other Tidbits
In googling I found this about GM's TMPS sensors:
70% Trigger For Warning Light
When a tire’s pressure drops from to 70% of the recommended cold inflation pressure (listed on the vehicle placard on the driver’s door opening, not the tire sidewall), the TPM warning light will illuminate to warn the driver of a low tire pressure condition.
OM p.99:
This light comes on briefly when the vehicle is started. It provides information about tire pressures and the TPMS.
Solid vs. Flahsing Warning Light
When the Light Is On Steady
This indicates that one or more of the tires are significantly underinflated.
A Driver Information Center (DIC) tire pressure message may also display. Stop as soon as possible, and inflate the tires to the pressure value shown on the Tire and Loading Information label. See Tire Pressure > 293.
When the Light Flashes First and Then Is On Steady
If the light flashes for about a minute and then stays on, there may be a problem with the TPMS. If the problem is not corrected, the light will come on every time the vehicle is started. See Tire Pressure Monitor Operation > 296.
With low tire pressure, the warning light on the instrument cluster will stay on solid and no system DTCs will be set. If the warning light flashes, there will be DTCs set, and there is a TPM system condition that needs diagnosis.
42% of Drivers Don't Know
A 2014 study by Schrader International, a company that manufactures TPMS systems, found that 42 percent of drivers are unable to identify the low tire-pressure warning light on the instrument cluster.
Roughly the same percentage of those polled admitted to rarely checking the tire pressure.
GM TPMS
GM TechLink
DIC, App Tire Pressure Display
The tire pressure readings can display in the Drivers Info Center (DIC)—OM p 108 —and also in the myChevroltte app. I like to have the tire display up all the time to catch a leaking tire before the alert goes off but day-to-day to maintain the correct tire pressure: 42 psi (OM p.295). If I see a drop a few psi I top it off. If it happens regularly, there may be a slow leak in the tire bead or even a nail in the tread.
If the tire is overinflated by more than 35 kPa (5 psi), the horn will sound multiple times and the turn signal lamp will continue to flash for several seconds after filling stops. To release and correct the pressure, while the turn signal lamp is still flashing, briefly press the center of the valve stem. When the recommended pressure is reached, the horn sounds once. OM p.298
Sensor Accuracy
In my experience it's not unusual to see a TPMS disagree with a manual gauge by a few psi. Of course then you get into the accuracy of the hand gauge as well. Maybe it's off a few psi.
You can compare the car's reading with a number of tire pressure gauges to see if there's a consensus of some sort. Or, you adjust and mentally add a few psi to what the TPMS displays. I'd like dead nuts accuracy, but the most important function is to alert on a big pressure drop indicating a severe puncture.
TPMS Sensor Matching Process — Auto Learn Function
Each TPMS sensor has a unique identification code. The identification code needs to be matched to a new tire/wheel position after rotating the tires or replacing one or more of the TPMS sensors. When a tire is installed, the vehicle must be stationary for about 20 minutes before the system recalculates. The following relearn process takes up to 10 minutes, driving at a minimum speed of 20 km/h (12 mph). A dash (-) or pressure value will display in the DIC. See Driver Information Center (DIC) > 108. A warning message displays in the DIC if a problem occurs during the relearn process. OM p.298
TPMS Sensor Matching Process — Manual Learn Function
- Each sensor has an internal low frequency coil. When a TPMS "relearn" tool is used in activate mode, it produces a low frequency transmission that activates the sensor. The sensor responds to a low frequency activation by transmitting in learn mode. When the TPMS antenna (in the box on the windshield) receives a learn mode transmission while in TPMS learn mode, it will assign that sensor’s ID number to the location on the vehicle relative to the order in which it was learned. A relearn tool need that supports 433MHz (I think). To place your Equinox in relearn mode use the steering wheel controls to display Options > Tire Pressure > Relearn (I think).
- When rotating tires, make sure the new tire locations are known by the car. The relearn tool does this and the whole process takes under a minute. OM p.298
- Aim at the sidewall below the valve stem, and not at the stem.
- 'If you can not get a sensor to initialize, try pushing the vehicle forward a foot or two. The signals can be blocked by components like rotors, calipers and knuckles. By repositioning the sensor, it may unblock the sensor. This is far more common on the front wheels.
- TIP: In order to prevent possible electrostatic discharge damage to the TPM Sensor, technicians should be statically discharged before checking or filling tires.
Other Tidbits
In googling I found this about GM's TMPS sensors:
- Sensors have a 10 year /150,000 mile (240,000 km) battery life.
- Each sensor takes a pressure measurement sample once every 30 seconds while in stationary mode. If the tire pressure increases or decreases by more than 1.2 psi from the last pressure measurement, another measurement will occur immediately to verify the change in pressure. If a pressure change has indeed occurred, the sensor transmits in Learn mode.
70% Trigger For Warning Light
When a tire’s pressure drops from to 70% of the recommended cold inflation pressure (listed on the vehicle placard on the driver’s door opening, not the tire sidewall), the TPM warning light will illuminate to warn the driver of a low tire pressure condition.
OM p.99:
This light comes on briefly when the vehicle is started. It provides information about tire pressures and the TPMS.
Solid vs. Flahsing Warning Light
When the Light Is On Steady
This indicates that one or more of the tires are significantly underinflated.
A Driver Information Center (DIC) tire pressure message may also display. Stop as soon as possible, and inflate the tires to the pressure value shown on the Tire and Loading Information label. See Tire Pressure > 293.
When the Light Flashes First and Then Is On Steady
If the light flashes for about a minute and then stays on, there may be a problem with the TPMS. If the problem is not corrected, the light will come on every time the vehicle is started. See Tire Pressure Monitor Operation > 296.
With low tire pressure, the warning light on the instrument cluster will stay on solid and no system DTCs will be set. If the warning light flashes, there will be DTCs set, and there is a TPM system condition that needs diagnosis.
42% of Drivers Don't Know
A 2014 study by Schrader International, a company that manufactures TPMS systems, found that 42 percent of drivers are unable to identify the low tire-pressure warning light on the instrument cluster.
Roughly the same percentage of those polled admitted to rarely checking the tire pressure.
GM TPMS
GM TechLink