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Home >> Toyota >> 2007 >> Prius Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Warning Systems >> 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 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: It is necessary to register an ID code after replacing the tire pressure warning valve and transmitter and/or the tire pressure warning ECU (see REGISTRATION  ).
  1. IDENTIFY TRANSMITTER (CORRESPONDING TO DTC) 
    1. Set the pressure of each tire to the specified value.

      Standard pressure 

      TIRE PRESSURE SPECIFICATION

      Front Rear
      240 kPa (2.4 kgf/cm2 , 35 psi) 230 kPa (2.3 kgf/cm2 , 33 psi)
    2. Connect the intelligent tester (with CAN VIM) to the DLC3.
    3. Turn the power switch ON (IG).
    4. Select TIREPRESS by following the prompts displayed on the intelligent tester.

      Tire pressure warning ECU 

      TIRE PRESSURE SPECIFICATION

      Item Measurement Item / Range (Display) Normal Condition Diagnostic Note
      TIREPRESS1 ID1 tire pressure/ minimum: 0 kPa (0 kgf/cm2 , 0 psi) maximum: 637.5 kPa (6.5 kgf/cm2 , 92.5 psi) Actual tire pressure -
      TIREPRESS2 ID2 tire pressure/ minimum: 0 kPa (0 kgf/cm2 , 0 psi) maximum: 637.5 kPa (6.5 kgf/cm2 , 92.5 psi) Actual tire pressure -
      TIREPRESS3 ID3 tire pressure/ minimum: 0 kPa (0 kgf/cm2 , 0 psi) maximum: 637.5 kPa (6.5 kgf/cm2 , 92.5 psi) Actual tire pressure -
      TIREPRESS4 ID4 tire pressure/ minimum: 0 kPa (0 kgf/cm2 , 0 psi) maximum: 637.5 kPa (6.5 kgf/ cm2 , 92.5 psi) Actual tire pressure -
    5. Rapidly release the tire pressure from any tire by 40 kPa (0.4 kgf/cm2 , 5.8 psi) for 30 seconds or more.

      HINT:

      • Identify the malfunctioning tire pressure warning valve and transmitter by rapidly releasing the tire pressures from each tire.
      • Record which TIREPRESS data (ID1 to ID5) corresponds to each tire.
    6. Check the DATA LIST.

      Result 

      DATA LIST RESULT REFERENCE

      Condition Detection Condition
      One of TIREPRESS data (ID1 to ID4) changed Normal
      No TIREPRESS data changed Transmitter corresponding to DTC
      NOTE:
      • It may take up to 1 minute to display the updated tire pressure data.
      • When the TIREPRESS data (IDs 1 to 4) changes, reset the tire pressure of the tires to the specified value, rotate the tires 90 to 270° and recheck.
      • When the transmitter is normal, record the tire location and the transmitter ID.
    7. When the TIREPRESS data (IDs 1 to 4) changes, repeat the same procedure on the rest of the tires (one by one) to identify which TIRE PRESSURE WARNING VALVE AND TRANSMITTER  the DTC corresponds to.
    8. Set the pressure of each tire to the specified value.

      Standard pressure 

      TIRE PRESSURE SPECIFICATION

      Front Rear
      240 kPa (2.4 kgf/cm2 , 35 psi) 230 kPa (2.3 kgf/cm2 , 33 psi)
    9. Check all transmitters of the tires.

      Result 

      TRANSMITTERS AND TIRES RESULT REFERENCE

      Result Detection Condition
      One or more of transmitters abnormal A
      All abnormal B
      All normal C

    B: Go to step  3

    C: END 

    A: Go to next step. 

  2. CHECK TIRE PRESSURE WARNING VALVE AND TRANSMITTER 
    1. Select REGIT ID CODE by following the prompts displayed on the intelligent tester.

      Tire pressure warning ECU 

      TIRE PRESSURE WARNING ECU SPECIFICATION

      Item Measurement Item / Range (Display) Normal Condition Diagnostic Note
      REGIT ID1 CODE Registered ID1 code/ minimum: 0 maximum: FFFFFFF The ID No. registered in transmitter ID1 is display -
      REGIT ID2 CODE Registered ID2 code/ minimum: 0 maximum: FFFFFFF The ID No. registered in transmitter ID2 is display -
      REGIT ID3 CODE Registered ID3 code/ minimum: 0 maximum: FFFFFFF The ID No. registered in transmitter ID3 is display -
      REGIT ID4 CODE Registered ID4 code/ minimum: 0 maximum: FFFFFFF The ID No. registered in transmitter ID4 is display -
    2. Remove the tire pressure warning valve and transmitter and check its ID number (see REMOVAL  ).
    3. Check whether the recorded transmitter ID and the actual transmitter ID match.

      Result 

      RESULT REFERENCE CHART

      Result Detection Condition
      Unmatched A
      Matched B

    B: REPLACE TIRE PRESSURE WARNING VALVE AND TRANSMITTER 

    Fig 1: Checking Transmitter ID Number
    G05189147Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    A: PERFORM REGISTRATION (TRANSMITTER ID) 

  3. CHECK WIRE HARNESS (ECU - RECEIVER) 
    Fig 2: Disconnecting T11 ECU Connector And T10 Receiver Connector
    G05189148Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the T11 ECU connector.
    2. Disconnect the T10 receiver connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      RESISTANCE REFERENCE CHART

      Tester Connection Specified Condition
      T11-10 (RF5V) - T10-5 (+5V) Below 1 Ω
      T11-9 (RDA) - T10-1 (RDA)
      T11-4 (GND2) - T10-4 (GND)

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step. 

  4. READ VALUE OF INTELLIGENT TESTER (TIRE PRESSURE) 
    1. Check the DATA LIST tire pressure valve.

      Tire pressure warning ECU 

      TIRE PRESSURE WARNING ECU SPECIFICATION

      Item Measurement Item / Range (Display) Normal Condition Diagnostic Note
      TIREPRESS1 ID1 tire pressure/ minimum: 0 kPa (0 kgf/cm2 , 0 psi) maximum: 637.5 kPa (6.5 kgf/cm2 , 92.5 psi) Actual tire pressure -
      TIREPRESS2 ID2 tire pressure/ minimum: 0 kPa (0 kgf/cm2 , 0 psi) maximum: 637.5 kPa (6.5 kgf/cm2 , 92.5 psi) Actual tire pressure -
      TIREPRESS3 ID3 tire pressure/ minimum: 0 kPa (0 kgf/cm2 , 0 psi) maximum: 637.5 kPa (6.5 kgf/cm2 , 92.5 psi) Actual tire pressure -
      TIREPRESS4 ID4 tire pressure/ minimum: 0 kPa (0 kgf/cm2 , 0 psi) maximum: 637.5 kPa (6.5 kgf/cm2 , 92.5 psi) Actual tire pressure -

      OK: All tire pressure readings are equal to the actual tire pressure. 

      NOTE: It may take up to 1 minute to display the updated tire pressure data.

    OK: END 

    NG: Go to next step. 

  5. CHECK ID CODE (TIRE PRESSURE WARNING VALVE AND TRANSMITTER) 
    1. Select REGIT ID CODE by following the prompts displayed on the intelligent tester.

      Tire pressure warning ECU 

      TIRE PRESSURE WARNING ECU SPECIFICATION

      Item Measurement Item / Range (Display) Normal Condition Diagnostic Note
      REGIT ID1 CODE Registered ID1 code/minimum: 0 maximum: FFFFFFF The ID No/registered in transmitter ID1 is display -
      REGIT ID2 CODE Registered ID2 code/minimum: 0 maximum: FFFFFFF The ID No. registered in transmitter ID2 is display -
      REGIT ID3 CODE Registered ID3 code/ minimum: 0 maximum: FFFFFFF The ID No. registered in transmitter ID3 is display -
      REGIT ID4 CODE Registered ID4 code/ minimum: 0 maximum: FFFFFFF The ID No. registered in transmitter ID4 is display -
    2. Remove the tire pressure monitor valve and check its ID number (see REMOVAL  ).
    3. Check whether the recorded transmitter ID and the actual transmitter ID match.

      Result 

      RESULT REFERENCE CHART

      Result Detection Condition
      Unmatched A
      Matched B
      Fig 3: Checking Transmitter ID Number
      G05189147Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    B: REPLACE TIRE PRESSURE WARNING RECEIVER AND TRANSMITTER 

    A: PERFORM REGISTRATION (TRANSMITTER ID) 

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