C2121
TIRE PRESSURE MONITORING: TIRE PRESSURE WARNING SYSTEM: C2121-C2124, C2181-C2184; No Signal from Transmitter ID1; 2013 MY FR-S [03/2012 -]
C2121 - No Signal from Transmitter ID1
C2122 - No Signal from Transmitter ID2
C2123 - No Signal from Transmitter ID3
C2124 - No Signal from Transmitter ID4
C2181 - Transmitter ID1 not Received (Test Mode DTC)
C2182 - Transmitter ID2 not Received (Test Mode DTC)
C2183 - Transmitter ID3 not Received (Test Mode DTC)
C2184 - 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 tire pressures. The measured values are transmitted to the door control receiver in the vehicle as radio waves. 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 assembly illuminates.
The tire pressure warning valve and transmitters constantly send radio waves to the door control receiver.
Under the conditions below, the door control 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 a tire pressure warning valve and transmitter is mistyped during registration.
* A tire, wheel and/or 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 20 minutes while the vehicle speed is more than 37 km/h (23 mph), or no transmitter ID is received from all the tire pressure warning valve and transmitters for a total of 20 minutes, these DTCs are set.
DTCs from C2121 to C2124 can only be cleared by using the Techstream. DTCs from C2181 to C2184 can be cleared when the tire pressure warning valve and transmitter sends a forced transmission signal or test mode ends. DTCs from C2181 to C2184 are output only in test mode.
NOTICE:
When DTCs C2121 to C2124 are set, DTC C2179 may be set simultaneously. In such cases, troubleshoot DTCs C2121 to C2124 first, then troubleshoot DTC C2179.
HINT
It is necessary to perform the following 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 door control receiver, read the IDs stored in the old ECU using the Techstream and write them down before removal.
* It is necessary to perform registration Programming and Relearning of the transmitter IDs into the tire pressure warning ECU after the ECU has been replaced.
* When replacing the door control receiver on vehicles, be sure to perform Registration of Recognition Code to register the transmitter IDs after ECU replacement Registration.
PROCEDURE
1. CHECK FREQUENCY RECEIVING CONDITION
(a) Check that the vehicle is not 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 such as the one 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 transmissions may be interrupted due to the 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 specified values Component Tests and General Diagnostics.
(b) Turn the ignition switch off.
(c) Connect the Techstream to the DLC3.
(d) Turn the ignition switch to ON.
(e) Turn the Techstream on.
(f) Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
(g) Check the values by referring to the table below.
Tire Pressure Monitor
HINT
*: It may take a few minutes until the values are displayed.
(h) Rapidly reduce the tire pressure for each wheel at least 40 kPa (0.4 kg/cm2, 5.8 psi) within 30 seconds.
(i) Check the Data List.
NOTICE:
* It may take a few 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 degrees. Then rapidly release the tire pressure and recheck the data.
* Record the transmitter ID of which "ID Tire Inflation Pressure" data corresponds to each tire.
(j) After confirming that the "ID Tire Inflation Pressure" 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 -- Continue to next step.
3. CHECK TRANSMITTER ID
(a) Turn the ignition switch off.
(b) Connect the Techstream to the DLC3.
(c) Turn the ignition switch to ON.
(d) Turn the Techstream on.
(e) Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
(f) Check the values by referring to the table below.
Tire Pressure Monitor
HINT
*: Displayed only when the ID No. is not registered.
(g) Check the ID number on the identified transmitter by removing it from the tire and wheel.
(h) Confirm that the ID number on the transmitter and recorded transmitter ID match.
Result:
B -- REGISTRATION OF TRANSMITTER ID
A -- Continue to next step.
4. REPLACE TIRE PRESSURE WARNING VALVE AND TRANSMITTER
(a) Replace the tire pressure warning valve and transmitter Removal.
NEXT -- Continue to next step.
5. REGISTRATION OF TRANSMITTER ID
(a) Perform registration Programming and Relearning.
NEXT -- Continue to next step.
6. CONFIRM TIRE INFLATION PRESSURE (DATA LIST)
(a) Turn the ignition switch off.
(b) Connect the Techstream to the DLC3.
(c) Turn the ignition switch to ON.
(d) Turn the Techstream on.
(e) Enter the following menus: Chassis / Tire Pressure Monitor / Data List.
(f) Check the values by referring to the table below.
Tire Pressure Monitor
HINT
* *: It may take a few minutes until the values are displayed.
* When no "ID Tire Inflation Pressure" 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 the data.
Result:
B -- END
A -- REPLACE DOOR CONTROL RECEIVER Removal