Do C8 TPMS ever go to sleep?
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Do C8 TPMS ever go to sleep?
EDIT - See post 3 below from GM tech buddy. They do go to "stationary mode" but sample pressure even stationary. They only report to Onstar if there's a drop.
Cliff's - Do C8 TPMS ever shut down to save battery? Or is the car always talking to Onstar?
Story - Went to go to a toys for tots event Saturday AM and upon starting car it shows RR at 27 PSI. I drive down the street and back to see if TPMS updates, it doesn't. Get out and see screw in tire. Pump it up to 34, throw my old C5 Z06 oem inflator kit in frunk and go about my day. All good... end of day it's 31.
Sunday I do family and yard work stuff.
This AM I'm out running and get a text and email stating RR tire pressure is low at 21 PSI. Mind you I haven't touched the car since parking Saturday late afternoon.
This means the TPMS are reading even when the car is static and the car is possibly "always" talking to Onstar?
I ask because I remember C7 TPMS shut down to save battery life and you have to drive a few minutes for the spinning tire to energize them. Is that no longer the case?
Creepy that my car is constantly beaming out data and concerning for battery life. Granted I drive the car every few days at a minimum and if it sits more than a week it's on a tender.
Cliff's - Do C8 TPMS ever shut down to save battery? Or is the car always talking to Onstar?
Story - Went to go to a toys for tots event Saturday AM and upon starting car it shows RR at 27 PSI. I drive down the street and back to see if TPMS updates, it doesn't. Get out and see screw in tire. Pump it up to 34, throw my old C5 Z06 oem inflator kit in frunk and go about my day. All good... end of day it's 31.
Sunday I do family and yard work stuff.
This AM I'm out running and get a text and email stating RR tire pressure is low at 21 PSI. Mind you I haven't touched the car since parking Saturday late afternoon.
This means the TPMS are reading even when the car is static and the car is possibly "always" talking to Onstar?
I ask because I remember C7 TPMS shut down to save battery life and you have to drive a few minutes for the spinning tire to energize them. Is that no longer the case?
Creepy that my car is constantly beaming out data and concerning for battery life. Granted I drive the car every few days at a minimum and if it sits more than a week it's on a tender.
Last edited by RapidC84B; Dec 12, 2022 at 05:57 PM.
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From: Garden Valley CA
^^^
Tire pressure sensors only sense the pressure inside the tire. It would be interesting to find out if the C8 BCM compensates for barometric pressure when it converts the data to tire pressure. I know people with C7s had problems at altitude where they would inflate the tires using a pressure gage but the system would think the tire pressure was lower.
Tire pressure sensors only sense the pressure inside the tire. It would be interesting to find out if the C8 BCM compensates for barometric pressure when it converts the data to tire pressure. I know people with C7s had problems at altitude where they would inflate the tires using a pressure gage but the system would think the tire pressure was lower.
