# Tpms **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [May 4, 2010, 12:15am UTC](https://community.cartalk.com/t/tpms/48357 "2010-05-04T00:15:56Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![JamieFR](https://avatars.discourse-cdn.com/v4/letter/j/c57346/32.png) [@JamieFR](https://community.cartalk.com/u/JamieFR)\ **Post date:** [May 4, 2010, 12:15am UTC](https://community.cartalk.com/t/tpms/48357/1 "2010-05-04T00:15:56Z")
I think I know the answer to this question, but once again I will ask experts. 2009 Hyundai Accent, just under 17k. Four days ago I had a nail removed from one of my tires and they patched the hole. This afternoon as I am leaving from work I notice the TPMS indicator light has come on as I am driving. As experts recommend elsewhere here I checked my owners manual but it says take it to the dealer. I should, however, be able to take it back to the shop and have them check it, correct? Also, this is not something that I will have to take care of like right now, as my tires are not flat (I am going to check the pressure in all, including the spare, as a precaution, in a bit), as the system is just a monitoring device, right? ---
**Author:** ![gpskibum](https://avatars.discourse-cdn.com/v4/letter/g/7feea3/32.png) [@gpskibum](https://community.cartalk.com/u/gpskibum)\ **Post date:** [May 4, 2010, 12:30am UTC](https://community.cartalk.com/t/tpms/48357/2 "2010-05-04T00:30:42Z")
Just for monitoring. If you check with a gauge and all is good then you have a sensor issue. Better off going back to who di the repair. The sensor is fairly large in the tire, part of valve stem assembly maybe it got damaged during repair. ---
**Author:** ![edb1961](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/edb1961/32/122_2.png) [@edb1961](https://community.cartalk.com/u/edb1961)\ **Post date:** [May 4, 2010, 1:16am UTC](https://community.cartalk.com/t/tpms/48357/3 "2010-05-04T01:16:09Z")
My wife’s 06 Toyota Sienna has a passive TPMS system that uses the ABS system. I think the principle is that a tire with low pressure rotates at a different speed from a fully inflated tire. The TPMS senses this and turns on the warning light. My 2010 Cobalt has a pressure sensor in each tire to directly measure the tire pressure. Both systems have to be reset after a tire repair, replacement, or rotation. The Sienna has a button to reset the system. The Cobalt has to relearn each tire in a rather complicated procedure. For now check each tire with a good quality dial type gauge, it’s difficult to tell if a tire has enough pressure from a visual check. Don’t assume the repair shop is going to set the correct pressure. I would check the Owner’s manual again, it took a while to find the reset procedure for the Sienna (+500 page manual). Ed B. ---
**Author:** ![Caddyman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/caddyman/32/23_2.png) [@Caddyman](https://community.cartalk.com/u/Caddyman)\ **Post date:** [May 4, 2010, 2:42am UTC](https://community.cartalk.com/t/tpms/48357/4 "2010-05-04T02:42:59Z")
TPMS. If it works, fine. If it does not work, black tape. Or you could spend half a day at the dealers shop while they fiddle with it…