TPMS Troubleshooting

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by TheRuffHouse, Jun 21, 2026 at 4:44 PM.

  1. TheRuffHouse

    TheRuffHouse New Member

    Joined:
    Yesterday
    2
    0
    0
    Location:
    Hohenwald, TN
    Vehicle:
    2008 Prius
    Model:
    Two
    Hi all,
    Long time listener, first time caller. I have a 2008 Prius Base, that I replaced the TPMS sensors on. I will admit they're cheap Amazon sensors. The computer can see them and their associated ID numbers and the computer can see their pressures and temperatures. But when I try to scan them for diagnostics, they fail, saying they don't respond. I cannot get the light on the dash to turn off, what am I missing here?
     
    #1 TheRuffHouse, Jun 21, 2026 at 4:44 PM
  2. Brian1954

    Brian1954 Senior Member

    Joined:
    Jan 31, 2021
    2,589
    1,029
    0
    Location:
    South Central PA, USA
    Vehicle:
    2011 Prius
    Model:
    III
    What computer are you talking about?
    What are you using to scan the TPMS sensors?
     
    #2 Brian1954, Jun 21, 2026 at 7:14 PM
  3. TheRuffHouse

    TheRuffHouse New Member

    Joined:
    Yesterday
    2
    0
    0
    Location:
    Hohenwald, TN
    Vehicle:
    2008 Prius
    Model:
    Two
    I took the car to Discount Tire and they scanned the sensors and "loaded" them into the TPMS Computer. I took a picture of the sensor IDs from their scanner.

    I am using an Autel MaxiAP200 Bluetooth OBD Scanner. I don't know exactly what module of the car I'm in when I read the data. Before I had the sensors installed, the Tire Pressure would read "0" or "-" in every corner. After having the sensors installed, they read the pressure and temperature, but it's odd to me that the light is still on. If I open the TPMS function (which I'm assuming is the TPMS module), it doesn't show any faults. Not sure what is happening here.
     
    #3 TheRuffHouse, Jun 21, 2026 at 7:47 PM
  4. pasadena_commut

    pasadena_commut Senior Member

    Joined:
    May 2, 2019
    2,980
    924
    0
    Location:
    Southern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Each sensor has a low pressure setting. For the sake of argument, let's say it should be 27 psi but is set to 35 psi on at least one of yours. If that the pressure was 34 psi it would turn on the tpms light. So you need to be sure all those low pressure settings are appropriate. I know where that is in Techstream, presumably it is somewhere in the braking section for the AP200 too. In theory you could set that low limit different for the front than the back, and only a few pounds less than the optimal tire pressure, but it isn't a great idea because when the tires are rotated one of the tires will probably be out of range. Maybe use 28 or 29 psi on all tires. 30 seems awfully close to 32 but I suppose if one kept religiously on top of tire pressure it would be OK. 31 is just begging for a TPMS light.

    There is also a TPMS reset button under the steering wheel, maybe you need to do that procedure if the lower limits are already OK and the pressures are good.
     
    #4 pasadena_commut, Jun 22, 2026 at 2:17 PM
  5. Brian1954

    Brian1954 Senior Member

    Joined:
    Jan 31, 2021
    2,589
    1,029
    0
    Location:
    South Central PA, USA
    Vehicle:
    2011 Prius
    Model:
    III
    I will take you through this troubleshooting one step at a time.

    When you turn the car on (Ready),
    1. does the tire pressure warning light flash on/off for 30 to 60 seconds, and then the light stays on.
    OR
    2. does the tire pressure warning light come on without flashing?
     
    #5 Brian1954, Jun 22, 2026 at 3:12 PM
(You must log in or sign up to post here.)