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 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 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 transmitter installed in each tire and wheel assembly measures the tire pressure. The measured values are transmitted as radio waves to the tire pressure warning antenna on the body and then set to the tire pressure warning ECU and receiver. 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 comes on. The tire pressure warning ECU stores a DTC when a tire pressure warning valve and transmitter stops transmitting signals.

Under the following conditions below, the tire pressure warning antenna 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 20 minutes while the vehicle speed is more than 8 km/h (5 mph) or no transmitter ID is received from all of the tire pressure warning valve and transmitters for a total of 20 minutes, DTCs are stored.

DTCs from C2121/21 to C2124/24 or C2131/31 to C2134/34 can only be cleared by using the Techstream. 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 this procedure to identify the malfunctioning tire pressure warning valve and transmitter as it cannot be identified only by the output DTC.