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Home >> Lexus >> 2007 >> GS 430 >> Repair and Diagnosis (Single Page) >> Suspension >> Wheels & Tire System >> Tire & Wheel >> 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 C2131/31 No Signal from Transmitter ID1 in 2nd Mode; DTC C2132/32 No Signal from Transmitter ID2 in 2nd Mode; DTC C2133/33 No Signal from Transmitter ID3 in 2nd Mode; DTC C2134/34 No Signal from Transmitter ID4 in 2nd 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) >> Inspection Procedure
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Inspection Procedure

NOTE:
  • When replacing the tire pressure warning ECU, read the IDs stored in the old ECU using the intelligent tester and write them down before removal.
  • It is necessary to perform INITIALIZATION  after REGISTRATION  of the transmitter IDs into the tire pressure warning ECU after the ECU and/or valve and transmitter has been replaced.
  1. CHECK FREQUENCY RECEIVING CONDITION 
    1. Check if the vehicle is located in areas such as the ones described below:
      1. Facilities or devices that use similar radio frequencies are located in the vicinity of the vehicle.

        HINT:

        If the vehicle is located in areas described above, the tire pressure warning light may come 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 the vicinity of the vehicle. 

        HINT:

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

    NG: CHECK IF ANY DEVICE IS INSTALLED BY USER 

    OK: Go to next step 

  2. IDENTIFY TRANSMITTER CORRESPONDING TO DTC 
    1. Set the tire pressure to the appropriate specified values (see INSPECTION ).
    2. Turn the engine switch off.
    3. Connect the intelligent tester to the DLC3.
    4. Turn the engine switch on (IG) and the tester ON.
    5. Following the display on the intelligent tester, select the "DATA LIST".
    6. Check the values by referring to the table below.

      Tire pressure warning ECU 

      TIRE PRESSURE WARNING ECU - DATA LIST

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      TIREPRESS1 ID1 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      TIREPRESS2 ID2 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      TIREPRESS3 ID3 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 ,0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      TIREPRESS4 ID4 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      HINT:
      *: It may take about 2 or 3 minutes until the values are displayed.
    7. Rapidly reduce the tire pressure for each wheel at least 40 kPa (0.4 kgf/cm2 , 5.8 psi) within 30 seconds.
    8. Check the DATA LIST.
      NOTE:
      • It takes about 2 or 3 minutes to display the updated tire pressure data.
      • When no "TIREPRESS" 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 "TIREPRESS" data transmitter ID that corresponds to each tire.
    9. After confirming that the "TIREPRESS" data for one tire (ID1 to ID4) has changed, repeat this procedure one by one. Identify the transmitter that corresponds to the DTC.

    Result 

    RESULT REFERENCE

    Condition Proceed to
    All tire pressure readings are equal to specified values A
    Any of tire pressure values are not displayed B
    All tire pressure values are not displayed C

    A: END 

    B:  Go to step  6

    C: Go to next step 

  3. SWITCH TIRE PRESSURE WARNING SELECT SWITCH 
    1. Switch the tire pressure warning select switch to the other position (MAIN to 2nd or 2nd to MAIN).
    2. Set the tire pressure to the appropriate specified values (see INSPECTION ).
    3. Turn the engine switch off.
    4. Connect the intelligent tester to the DLC3.
    5. Turn the engine switch on (IG) and the tester ON.
    6. Following the display on the intelligent tester, select the "DATA LIST".
    7. Check the values by referring to the table below.

      Tire pressure warning ECU 

      TIRE PRESSURE WARNING ECU - DATA LIST

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      TIREPRESS1 ID1 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure /637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      TIREPRESS2 ID2 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      TIREPRESS3 ID3 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      TIREPRESS4 ID4 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      HINT:
      *: It may take about 2 or 3 minutes until the values are displayed.
    8. Rapidly reduce the tire pressure for each wheel at least 40 kPa (0.4 kgf/cm2 , 5.8 psi) within 30 seconds.
    9. Check the DATA LIST.
      NOTE:
      • It takes about 2 or 3 minutes to display the updated tire pressure data.
      • When no "TIREPRESS" 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 "TIREPRESS" data transmitter ID that corresponds to each tire.
    10. After confirming that the "TIREPRESS" data for one tire (ID1 to ID4) has changed, repeat this procedure one by one. Identify the transmitter that corresponds to the DTC.

    Result 

    RESULT REFERENCE

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

    A: END 

    B: Go to next step 

  4. RETURN TIRE PRESSURE WARNING SELECT SWITCH TO ORIGINAL POSITION 
    1. Return tire pressure warning select switch to the original position.
  5. CHECK HARNESS AND CONNECTOR (ECU - RECEIVER) 
    1. Disconnect the K45 ECU connector.
    2. Disconnect the U34 receiver connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      K45-9 (RDA) - U34-1 (RDA) Always Below 1 Ω
      K45-4 (GND2) - U34-4 (GND)
      K45-10 (RF5V) - U34-5 (+5V)
      K45-9 (RDA) - Body ground Always 10 kΩ or higher
      K45-4 (GND2) - Body ground
      K45-10 (RF5V) - Body ground
    Fig 1: Identifying K45 ECU And U34 Receiver Connector
    G05296827Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  6. INSPECT TIRE PRESSURE WARNING ANTENNA AND RECEIVER 
    1. Turn the engine switch off.
    2. Connect the intelligent tester to the DLC3.
    3. Turn the engine switch on (IG) and the tester ON.
    4. Following the display on the intelligent tester, select the "DATA LIST".
    5. Check the values by referring to the table below.

      Tire pressure warning ECU 

      TIRE PRESSURE WARNING ECU - DATA LIST

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      REGIT ID1 CODE Registered ID1 code/
      min.: 0
      max.: FFFFFFF*      		 The ID No. registered in the transmitter ID1 is displayed *: Displayed only when the ID No. is not registered.
      REGIT ID2 CODE Registered ID2 code/
      min.: 0
      max.: FFFFFFF*      		 The ID No. registered in the transmitter ID2 is displayed *: Displayed only when the ID No. is not registered.
      REGIT ID3 CODE Registered ID3 code/
      min.: 0
      max.: FFFFFFF*      		 The ID No. registered in the transmitter ID3 is displayed *: Displayed only when the ID No. is not registered.
      REGIT ID4 CODE Registered ID4 code/
      min.: 0
      max.: FFFFFFF*      		 The ID No. registered in the transmitter ID4 is displayed *: Displayed only when the ID No. is not registered.
    6. Check the ID number on the identified transmitter by removing it from the tire and wheel.
      Fig 2: Identifying Transmitter ID (7 Digit Number)
      G04944270Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Confirm that the ID number on the transmitter and recorded transmitter ID match.

      Result 

      RESULT REFERENCE

      Result Proceed to
      Match A
      Do not match B

    B:  Go to step  8

    A: Go to next step 

  7. REPLACE TIRE PRESSURE WARNING VALVE AND TRANSMITTER 
    1. Replace tire pressure warning valve and transmitter (see TIRE PRESSURE WARNING VALVE AND TRANSMITTER COMPONENTS ).
  8. REGISTRATION OF TRANSMITTER ID 
    1. Perform REGISTRATION  .
  9. PERFORM INITIALIZATION 
    1. Perform INITIALIZATION  .
  10. CONFIRM TIRE INFLATION PRESSURE (DATA LIST) 
    1. Turn the engine switch off, and then turn it on (IG).
    2. Following the display on the intelligent tester, select the "DATA LIST".
    3. Check the values by referring to the table below.

    Tire pressure warning ECU 

    TIRE PRESSURE WARNING ECU - DATA LIST

    Tester Display Measurement Item/Range Normal Condition Diagnostic Note
    TIREPRESS1 ID1 tire inflation pressure /
    min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
    max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)    		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
    or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
    TIREPRESS2 ID2 tire inflation pressure /
    min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
    max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)    		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
    or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
    TIREPRESS3 ID3 tire inflation pressure /
    min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
    max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)    		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
    or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
    TIREPRESS4 ID4 tire inflation pressure /
    min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
    max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)    		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
    or-100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
    HINT:
    *: It may take about 2 or 3 minutes until the values are displayed.

    Result 

    RESULT REFERENCE

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

    A: END 

    B: Go to next step 

  11. REPLACE TIRE PRESSURE WARNING ANTENNA AND RECEIVER 
    1. Replace the tire pressure warning antenna and receiver (see REPLACEMENT ).
  12. CONFIRM TIRE INFLATION PRESSURE (DATA LIST) 
    1. Turn the engine switch off, and then turn it on (IG). Following the display on the intelligent tester, select the "DATA LIST".
    2. Check the values by referring to the table below.

      Tire pressure warning ECU 

      TIRE PRESSURE WARNING ECU - DATA LIST

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      TIREPRESS1 ID1 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      TIREPRESS2 ID2 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 ,92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      TIREPRESS3 ID3 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      TIREPRESS4 ID4 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 637.5 kPa (6.5 kgf/cm2 , 92.5 psi), Relative pressure / 537.5 kPa (5.4 kgf/cm2 , 78 psi)      		 Actual tire inflation pressure If 0 kPa (0 kgf/cm2 , 0 psi) is displayed for absolute pressure
      or -100 kPa (-1 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      HINT:
      *: It may take about 2 or 3 minutes until the values are displayed.

      Result 

      RESULT REFERENCE

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

    B: REPLACE TIRE PRESSURE WARNING ECU (See  REPLACEMENT  ) 

    A: END 

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