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Home >> Lexus >> 2012 >> RX 350 FWD >> 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; DTC C2122/22: No Signal from Transmitter ID2; DTC C2123/23: No Signal from Transmitter ID3; DTC C2124/24: No Signal from Transmitter ID4; DTC C2125/25: No Signal from Transmitter ID5; 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); DTC C2185/85: Transmitter ID5 not Received (Test Mode DTC) >> Procedure
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DTC C2121/21: No Signal from Transmitter ID1; DTC C2122/22: No Signal from Transmitter ID2; DTC C2123/23: No Signal from Transmitter ID3; DTC C2124/24: No Signal from Transmitter ID4; DTC C2125/25: No Signal from Transmitter ID5; 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); DTC C2185/85: Transmitter ID5 not Received (Test Mode DTC): Procedure

  1. READ OUTPUT DTC (DTC C2173/73) 
    1. Turn the engine switch off.
    2. Connect Techstream to the DLC3.
    3. Turn the engine switch on (IG) and turn the tester on.
    4. Enter the following menus: Chassis / Tire Pressure Monitor / Trouble Codes.
    5. Read the 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 that the vehicle is located in an area such as 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 an area described above, the tire pressure warning light may turn on only in a particular area due to interfering radio frequencies.

      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 transmissions 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 to the appropriate specified values. Refer to INSPECTION - Step 1 .
    2. Turn the engine switch off.
    3. Connect Techstream to the DLC3.
    4. Turn the engine switch on (IG) and turn the tester 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID5 Tire Inflation Pressure ID5 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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 by 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 the "ID Tire Inflation Pressure" data has not 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 the data.
      • Record the "ID Tire Inflation Pressure" data transmitter ID that corresponds to each tire.
    9. After confirming that the "ID Tire Inflation Pressure" data for one tire (ID1 to ID5) has changed, repeat this procedure one by one. Identify the transmitter that corresponds to the DTC.

      Result

      Condition Proceed to
      All abnormal A
      One or more of 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 F53 ECU connector.
      Fig 1: F53 ECU & P34 Receiver Connector
      GTY357327Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the P34 receiver connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      F53-12 (RDA) - P34-1 (RDA) Always Below 1 Ω
      F53-11 (GND2) - P34-4 (GND) Always Below 1 Ω
      F53-6 (RF5V) - P34-5 (+5V) Always Below 1 Ω
      F53-12 (RDA) or P34-1 (RDA) - Body ground Always 10 kΩ or higher
      F53-11 (GND2) or P34-4 (GND) - Body ground Always 10 kΩ or higher
      F53-6 (RF5V) or P34-5 (+5V) - Body ground Always 10 kΩ or higher
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Tire Pressure Warning ECU)
      *2 Front view of wire harness connector
      (to Tire Pressure Warning Antenna and Receiver)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. CHECK TRANSMITTER ID 
    1. Turn the engine switch off.
    2. Connect Techstream to the DLC3.
    3. Turn the engine switch on (IG) and turn the tester on.
    4. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
    5. 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*      		 The ID No. registered in the transmitter ID1 is displayed *: Displayed only when the ID No. is not registered.
      Registered 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.
      Registered 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.
      Registered 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.
      Registered ID5 Code Registered ID5 code/
      min.: 0
      max.: FFFFFFF*      		 The ID No. registered in the transmitter ID5 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 Tire Pressure Warning Valve And Transmitter & 7 Digit ID
      GTY261340Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. 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. 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 engine switch off.
    2. Connect Techstream to the DLC3.
    3. Turn the engine switch on (IG) and turn the tester on.
    4. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
    5. 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID5 Tire Inflation Pressure ID5 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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.
      • When the "ID Tire Inflation Pressure" data has not 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 the data.

      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 engine switch off.
    2. Connect Techstream to the DLC3.
    3. Turn the engine switch on (IG) and turn the tester on.
    4. Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
    5. 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 kgf/cm2 , -14 psi) is displayed for relative pressure, data has not been received.*
      ID5 Tire Inflation Pressure ID5 tire inflation pressure /
      min.: Absolute pressure / 0 kPa (0 kgf/cm2 , 0 psi), Relative pressure / -100 kPa (-1.0 kgf/cm2 , -14 psi)
      max.: Absolute pressure / 638 kPa (6.5 kgf/cm2 , 93 psi), Relative pressure / 538 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 (-1.0 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.
      • When the "ID Tire Inflation Pressure" data has not 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 the data.

      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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