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Home >> Scion >> 2012 >> tC Standard Trans >> Repair and Diagnosis (Single Page) >> Suspension >> Wheels & Tire System >> Tire Pressure Warning System (Diagnostic Codes & Circuit Tests) >> Tire Pressure Warning System >> DTC C2121/21: No Signal from Transmitter ID1 in Main Mode; DTC C2122/22: No Signal from Transmitter ID2 in Main Mode; DTC C2123/23: No Signal from Transmitter ID3 in Main Mode; DTC C2124/24: No Signal from Transmitter ID4 in Main Mode; DTC C2181/81: Transmitter ID1 not Received (Test Mode DTC); DTC C2182/82: Transmitter ID2 not Received (Test Mode DTC); DTC C2183/83: Transmitter ID3 not Received (Test Mode DTC); DTC C2184/84: Transmitter ID4 not Received (Test Mode DTC) >> Procedure
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DTC C2121/21: No Signal from Transmitter ID1 in Main Mode; DTC C2122/22: No Signal from Transmitter ID2 in Main Mode; DTC C2123/23: No Signal from Transmitter ID3 in Main Mode; DTC C2124/24: No Signal from Transmitter ID4 in Main Mode; DTC C2181/81: Transmitter ID1 not Received (Test Mode DTC); DTC C2182/82: Transmitter ID2 not Received (Test Mode DTC); DTC C2183/83: Transmitter ID3 not Received (Test Mode DTC); DTC C2184/84: Transmitter ID4 not Received (Test Mode DTC): Procedure

  1. READ OUTPUT DTC (DTC C2173/73) 
    1. Turn the ignition switch off.
    2. Connect the Techstream to the DLC3.
    3. Turn the ignition switch to ON.
    4. Turn the Techstream on.
    5. Enter the following menus: Chassis / Tire Pressure Monitor / Trouble Codes.
    6. Read DTCs.
      RESULT

      Result Proceed to
      DTC C2173/73 is not output A
      DTC C2173/73 is output B
      NOTE:

      When DTC C2173/73 is output, troubleshoot that DTC first. Then troubleshoot DTCs C2121/21 to C2124/24.

    B → See step   13 

    A: Go to next step 

  2. CHECK FREQUENCY RECEIVING CONDITION 
    1. Check for the following conditions:
      1. Facilities or devices that use similar radio frequencies are located in the vicinity of the vehicle.

        HINT: 

        If the vehicle is located in an area described above, the tire pressure warning light may turn on only in a particular area.

      2. Devices using similar radio frequencies are used in the vehicle.

        OK

        Facilities or devices that use similar radio frequencies are not located in or around the vehicle.

        HINT: 

        Radio frequencies may be interrupted due to the surroundings or devices installed by the user.

    NG → CHECK IF ANY DEVICE IS INSTALLED BY USER 

    OK: Go to next step 

  3. IDENTIFY TRANSMITTER CORRESPONDING TO DTC 
    1. Set the tire pressure of all tires to the specified value. Refer to INSPECTION .
    2. Turn the ignition switch off.
    3. Connect the Techstream to the DLC3.
    4. Turn the ignition switch to ON.
    5. Turn the Techstream on.
    6. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
    7. Check the values by referring to the table below.
      TIRE PRESSURE MONITOR

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      ID1 Tire Inflation Pressure ID1 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID2 Tire Inflation Pressure ID2 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID3 Tire Inflation Pressure ID3 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID4 Tire Inflation Pressure ID4 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*

      HINT: 

      *: It may take up to a few minutes until the values are displayed.

    8. Rapidly reduce the tire pressure of each tire by at least 40 kPa (0.4 kgf/cm2 , 5.8 psi) within 30 seconds.
    9. Check the Data List.
      NOTE:
      • It may take up to a few minutes to display the updated tire pressure data.
      • When no "ID Tire Inflation Pressure" data has changed, reset the tire pressure to the appropriate specified value and rotate the tire 90 to 270°. Then rapidly release the tire pressure and recheck it.
      • Record the "ID Tire Inflation Pressure" data transmitter ID that corresponds to each tire.
    10. After confirming that the "ID Tire Inflation Pressure" data for one tire (ID1 to ID4) has changed, repeat this procedure for each tire. Identify the transmitter that corresponds to the DTC.
      RESULT

      Result Proceed to
      All abnormal A
      One or more transmitters abnormal B
      All normal C

    B → See step   5 

    C → END 

    A: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (ECU - RECEIVER) 
    1. Disconnect the C40 ECU connector.
    2. Disconnect the J11 receiver connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C40-12 (RDA) - J11-1 (RDA) Always Below 1 Ω
      C40-11 (GND2) - J11-4 (GND) Always Below 1 Ω
      C40-6 (RF5V) - J11-5 (+5V) Always Below 1 Ω
      C40-12 (RDA) or J11-1 (RDA) - Body ground Always 10 kΩ or higher
      C40-11 (GND2) or J11-4 (GND) - Body ground Always 10 kΩ or higher
      C40-6 (RF5V) or J11-5 (+5V) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. CHECK TRANSMITTER ID 
    1. Turn the ignition switch off.
    2. Connect the Techstream to the DLC3.
    3. Turn the ignition switch to ON.
    4. Turn the Techstream on.
    5. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
    6. Check the values by referring to the table below.
      TIRE PRESSURE MONITOR

      Tester Display Measurement Item/Display Normal Condition Diagnostic Note
      Registered ID1 Code Registered ID1 code/
      min.: 0
      max.: FFFFFFF*      		 ID No. registered in transmitter ID1 displayed *: Displayed only when the ID No. is not registered.
      Registered ID2 Code Registered ID2 code/
      min.: 0
      max.: FFFFFFF*      		 ID No. registered in transmitter ID2 displayed *: Displayed only when the ID No. is not registered.
      Registered ID3 Code Registered ID3 code/
      min.: 0
      max.: FFFFFFF*      		 ID No. registered in transmitter ID3 displayed *: Displayed only when the ID No. is not registered.
      Registered ID4 Code Registered ID4 code/
      min.: 0
      max.: FFFFFFF*      		 ID No. registered in transmitter ID4 displayed *: Displayed only when the ID No. is not registered.
    7. Check the ID number on the identified transmitter by removing it from the tire and wheel.
    8. Confirm that the ID number on the transmitter and recorded transmitter ID match.
      RESULT

      Result Proceed to
      Match A
      Do not match B

    B → See step   7 

    A: Go to next step 

  6. REPLACE TIRE PRESSURE WARNING VALVE AND TRANSMITTER 
    1. Replace the tire pressure warning valve and transmitter. Refer to REMOVAL .

    NEXT: Go to next step 

  7. PERFORM REGISTRATION OF TRANSMITTER ID 
    1. Perform registration. Refer to REGISTRATION .

    NEXT: Go to next step 

  8. PERFORM INITIALIZATION 
    1. Perform initialization. Refer to INITIALIZATION .

    NEXT: Go to next step 

  9. CONFIRM TIRE INFLATION PRESSURE (DATA LIST) 
    1. Turn the ignition switch off.
    2. Connect the Techstream to the DLC3.
    3. Turn the ignition switch to ON.
    4. Turn the Techstream on.
    5. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
    6. Check the values by referring to the table below.
      TIRE PRESSURE MONITOR

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      ID1 Tire Inflation Pressure ID1 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID2 Tire Inflation Pressure ID2 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID3 Tire Inflation Pressure ID3 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID4 Tire Inflation Pressure ID4 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*

      HINT: 

      • *: It may take up to a few minutes until the values are displayed.
      • When no "ID Tire Inflation Pressure" data has changed, reset the tire pressure to the appropriate specified value and rotate the tire 90 to 270°. Then rapidly release the tire pressure and recheck it.
      RESULT

      Result Proceed to
      Tire pressure values are not displayed A
      All tire pressure readings are equal to specified values B

    B → END 

    A: Go to next step 

  10. REPLACE TIRE PRESSURE WARNING ANTENNA AND RECEIVER 
    1. Replace the tire pressure warning antenna and receiver. Refer to REMOVAL .

    NEXT: Go to next step 

  11. CONFIRM TIRE INFLATION PRESSURE (DATA LIST) 
    1. Turn the ignition switch off.
    2. Connect the Techstream to the DLC3.
    3. Turn the ignition switch to ON.
    4. Turn the Techstream on.
    5. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
    6. Check the values by referring to the table below.
      TIRE PRESSURE MONITOR

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      ID1 Tire Inflation Pressure ID1 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID2 Tire Inflation Pressure ID2 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID3 Tire Inflation Pressure ID3 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID4 Tire Inflation Pressure ID4 tire inflation pressure /
      min.: Absolute pressure 0.0 kPa (0.0 kgf/cm2 , 0.0 psi), Relative pressure -100.0 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure 637.5 kPa (6.5 kgf/cm2 , 92 psi), Relative pressure 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0.0 kgf/cm2 , 0.0 psi) is displayed for absolute pressure or -100 kPa (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*

      HINT: 

      • *: It may take up to a few minutes until the values are displayed.
      • When no "ID Tire Inflation Pressure" data has changed, reset the tire pressure to the appropriate specified value and rotate the tire 90 to 270°. Then rapidly release the tire pressure and recheck it.
      RESULT

      Result Proceed to
      All tire pressure readings are equal to specified values A
      Tire pressure values are not displayed B

    B → See step   12 

    A → END 

  12. REPLACE TIRE PRESSURE WARNING ECU. Refer to  REMOVAL 
  13. GO TO DTC C2173/73. Refer to  DTC C2173/73: Vehicle Speed or Engine Speed Signal Malfunction  
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