From 03-2006 to 10-2006

TIRE AND WHEEL: TIRE PRESSURE WARNING SYSTEM: C2121/21-C2124/24,C2181/81-C2184/84: 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 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)

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 valves 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.

HINT:
When no signals are received for 51 minutes or more, a DTC is output.
DTCs from C2121/21 to C2124/24 can only be cleared by using the tester. DTCs from C2181/81 to C2184/84 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 C2184/84 are output only in test mode.

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 Initialization after registration Registration of the transmitter IDs into the tire pressure warning ECU after the ECU and/or valve and transmitter has been replaced.

PROCEDURE

1. CHECK FREQUENCY RECEIVING CONDITION
(a) Check if the vehicle is not located in 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.
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 -- Continue to next step.
2. IDENTIFY TRANSMITTER CORRESPONDING TO DTC
(a) Set the tire pressure to the appropriate specified values.

Cold tire inflation pressure:

(b) Select "TIREPRESS" by following the prompts displayed on the intelligent tester.

TIRE PRESSURE:

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

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 one of 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:

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

(a) Disconnect the E60 ECU connector.
(b) Disconnect the N20 receiver 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.
4. INSPECT TIRE PRESSURE WARNING VALVE AND TRANSMITTER
(a) Select REGIT ID CODE by following the prompts displayed on the intelligent tester.

TIRE PRESSURE:

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

B -- REGISTRATION OF TRANSMITTER ID
A -- Continue to next step.
5. REPLACE TIRE PRESSURE WARNING VALVE AND TRANSMITTER

HINT: Removal

NEXT -- Continue to next step.
6. REGISTRATION OF TRANSMITTER ID
(a) Perform registration Registration.
(b) Set the tire pressure to the appropriate specified values.

Cold tire inflation pressure:

NEXT -- Continue to next step.
7. PERFORM INITIALIZATION
(a) Perform initialization Initialization.
NEXT -- Continue to next step.
8. READ VALUE USING DATA LIST
(a) Turn the power switch off, and then turn it on (IG).
(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:

A -- END
B -- Continue to next step.
9. REPLACE TIRE PRESSURE WARNING ANTENNA AND RECEIVER
(a) Replace the tire pressure warning antenna and receiver Removal.
NEXT -- Continue to next step.
10. READ VALUE USING DATA LIST
(a) Turn the power switch off, and then turn it on (IG).
(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