C2124

TIRE AND WHEEL: TIRE PRESSURE WARNING SYSTEM: C2121/21: No Signal from Transmitter ID1 in Main Mode

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 C2125/25 - No Signal from Transmitter ID5 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 C2135/35 - No Signal from Transmitter ID5 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)

DTC C2185/85 - Transmitter ID5 not Received (Test Mode DTC)

DESCRIPTION

The tire pressure warning valve and transmitters that are installed in the tire and wheel assemblies measure the air pressure of the tires. The measured values are transmitted to the tire pressure warning antenna and receiver on the body as radio waves and then sent to the tire pressure warning ECU. The ECU compares the measured air pressure values with the air pressure threshold. When the measured air pressure value is less than this threshold, the warning light in the combination meter comes on.
The tire pressure warning valve and transmitters constantly send radio waves to the tire pressure warning antenna and receiver.
Under the following conditions below, the tire pressure warning antenna and receiver is unable to receive the signals from the tire pressure warning valve and transmitters, and a DTC is stored.

- Facilities or devices that use similar radio frequencies are located in the vicinity of the vehicle.
- Devices using similar radio frequencies are used in the vehicle.
- The ID of the tire pressure warning valve and transmitter is mistyped during registration.
- A tire/wheel/transmitter from a different vehicle is installed.
HINT: When no transmitter ID is received from a tire pressure warning valve and transmitter for a total of 51 minutes (For vehicles manufactured after August of 2007, it is 20 minutes) while the vehicle speed is more than 8 km/h (5 mph) or no transmitter ID is received from all the tire pressure warning valve for a total of 51 minutes (For vehicles manufactured after August of 2007, it is 20 minutes), DTCs are stored.
DTCs from C2121/21 to C2124/25 and C2131/31 to C2135/35 can only be cleared by using the Techstream. DTCs from C2181/81 to C2185/85 can be cleared when the transmitter in the tire pressure warning valve and transmitter sends a forced transmission signal or test mode ends. DTCs from C2181/81 to C2185/85 are output only in test mode.

*1: For vehicles manufactured after August of 2007, it is 20 minutes.
HINT: It is necessary to perform the procedure to identify the tire pressure warning valve and transmitter that is malfunctioning because it cannot be identified by the output DTC.

WIRING DIAGRAM

INSPECTION PROCEDURE
NOTICE:
- When replacing the tire pressure warning ECU, read the IDs stored in the 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 or valve and transmitter has been replaced.
HINT: Set the tire pressure to the specified value.

PROCEDURE

1. CHECK FREQUENCY RECEIVING CONDITION
(a) Check if the vehicle is not located in any areas 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 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.
HINT: Radio frequency may be interrupted due to surroundings or devices installed by users.

OK:
Facilities, or devices that use similar radio frequencies are not located in the vicinity of the vehicle.
NG -- CHECK IF ANY DEVICE IS INSTALLED BY USER
OK -- Continue to next step.
2. CHECK TIRE PRESSURE WARNING SELECT SWITCH
(a) Switch the tire pressure warning select switch to the other position (MAIN to 2nd or 2nd to MAIN).
HINT: If the IDs of the installed tire and wheel set and the select switch do not match, this DTC will be output.
(b) Read the values using DATA LIST.
(c) Select TIREPRESS by following the prompts displayed on the intelligent tester.
HINT: It may take up to 1 minute to display the tire pressure data.

Result:

B -- END
A -- Continue to next step.
3. RETURN TIRE PRESSURE WARNING SELECT SWITCH TO ORIGINAL POSITION
NEXT -- Continue to next step.
4. IDENTIFY TRANSMITTER CORRESPONDING TO DTC
(a) Set the tire pressure to the appropriate specified values.
Cold tire inflation pressure:

*1: For driving under 100 mph (160 km/h)
*2: For driving at 100 mph (160 km/h) or more
(b) Select "TIREPRESS" by following the prompts displayed on the intelligent tester.

(c) Rapidly reduce the tire pressure for each wheel by approximately 40 kPa (at least 40 kPa, 0.41 kgf/cm2, 5.8 psi within 30 seconds).
(d) Check the DATA LIST.
Result:

NOTICE:
- It takes about 1 minute or more 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 degrees. Then rapidly release the tire pressure and recheck it.
- Record the transmitter ID of which "TIREPRESS" data corresponds to each tire.
(e) After confirming that "TIREPRESS" data for one tire (ID1 to ID5) has changed, repeat this procedure one by one. Identify the transmitter that corresponds to a DTC.
Result:

B -- END
A -- INSPECT TIRE PRESSURE WARNING VALVE AND TRANSMITTER
C -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (ECU - RECEIVER)

(a) Disconnect the T23 connector.
(b) Disconnect the T25 connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
6. INSPECT TIRE PRESSURE WARNING VALVE AND TRANSMITTER
(a) Select REGIT ID CODE by following the prompts displayed on the intelligent tester.

(b) Check the ID number on the identified transmitter by removing it from the tire and wheel.

B -- PERFORM REGISTRATION (TRANSMITTER ID)
A -- Continue to next step.
7. REPLACE TIRE PRESSURE WARNING VALVE AND TRANSMITTER
(a) Replace the identified tire pressure warning valve and transmitter with a new one.
HINT:
- Before installing a new tire pressure warning valve and transmitter, read and write down its transmitter ID
- The IDs for the tire pressure warning valve and transmitter that have not been replaced should be checked using the tester and recorded.

NEXT -- Continue to next step.
8. PERFORM REGISTRATION (TRANSMITTER ID)
(a) Perform registration .
NEXT -- Continue to next step.
9. PERFORM INITIALIZATION
(a) Perform initialization .
(b) Set the tire air pressure of all wheels to the specified value.
Cold tire inflation pressure:

*1: For driving under 100 mph (160 km/h)
*2: For driving at 100 mph (160 km/h) or more
NEXT -- Continue to next step.
10. READ VALUE USING DATA LIST
(a) Turn the ignition switch off, and then turn it to the ON position.
(b) Select TIREPRESS by following the prompts displayed on the intelligent tester.
HINT: It may take up to 1 minute or more to display the tire pressure data.

Result:

B -- REPLACE TIRE PRESSURE WARNING ECU
A -- END