LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2017 >> Prius Four >> Repair and Diagnosis (Single Page) >> Suspension >> Wheels & Tire System >> Tire Pressure Warning System - Diagnostic Codes & Circuit Tests >> Tire Pressure Warning System >> DTC C2121: No Signal from Transmitter ID1; DTC C2122: No Signal from Transmitter ID2; DTC C2123: No Signal from Transmitter ID3; DTC C2124: No Signal from Transmitter ID4; DTC C2125: No Signal from Transmitter ID5; DTC C2181: Transmitter ID1 not Received (Test Mode DTC); DTC C2182: Transmitter ID2 not Received (Test Mode DTC); DTC C2183: Transmitter ID3 not Received (Test Mode DTC); DTC C2184: Transmitter ID4 not Received (Test Mode DTC); DTC C2185: Transmitter ID5 not Received (Test Mode DTC) [11/2015 - 12/2018] >> Description
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC C2121: No Signal from Transmitter ID1; DTC C2122: No Signal from Transmitter ID2; DTC C2123: No Signal from Transmitter ID3; DTC C2124: No Signal from Transmitter ID4; DTC C2125: No Signal from Transmitter ID5; DTC C2181: Transmitter ID1 not Received (Test Mode DTC); DTC C2182: Transmitter ID2 not Received (Test Mode DTC); DTC C2183: Transmitter ID3 not Received (Test Mode DTC); DTC C2184: Transmitter ID4 not Received (Test Mode DTC); DTC C2185: Transmitter ID5 not Received (Test Mode DTC) [11/2015 - 12/2018]: Description

The tire pressure warning valve and transmitters that are installed in the tire and wheel assemblies measure the tire pressure of each wheel. The measured values are transmitted to the tire pressure warning ECU and receiver in the vehicle as radio waves. The ECU compares the measured tire pressure values with the tire pressure threshold. When the measured tire 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 tire pressure warning ECU and receiver.

Under the conditions below, the tire pressure warning ECU and receiver is unable to receive the signals from the tire pressure warning valve and transmitters, and a DTC is stored.

HINT: 

When no transmitter ID is received from a tire pressure warning valve and transmitter for 20 minutes or more while the vehicle speed is more than 40 km/h (25 mph), or no transmitter ID is received from all of the tire pressure warning valve and transmitters for 20 minutes or more, DTCs from C2121 to C2124 (C2125: w/ Full Size Spare Tire) are stored.

DTCs C2121 to C2124 (C2125: w/ Full Size Spare Tire) can only be cleared by using the Techstream. DTCs C2181 to C2184 (C2185: w/ Full Size Spare Tire) can be cleared when the tire pressure warning valve and transmitter sends a forced transmission signal or test mode ends. DTCs C2181 to C2184 (C2185: w/ Full Size Spare Tire) are output only in test mode.

DTC No. Detection Item DTC Detection Condition Trouble Area Note
C2121 No Signal from Transmitter ID1 Either of the following conditions (a) or (b) is met:
(a) When all conditions below are met:
  • Tire pressure warning valve and transmitter is not in stop mode.
  • Any transmitter ID is not received from tire pressure warning valve and transmitters.
  • Vehicle speed is more than 40 km/h (25 mph) or no vehicle speed signal is received for 20 minutes or more.

(b) When both conditions below are met:
  • Tire pressure warning valve and transmitter is not in stop mode.
  • No transmitter ID is received from tire pressure warning valve and transmitters for 20 minutes or more.
  • Tire pressure warning valve and transmitter
  • Tire pressure warning ECU and receiver
DTC: 21
C2122 No Signal from Transmitter ID2 Either of the following conditions (a) or (b) is met:
(a) When all conditions below are met:
  • Tire pressure warning valve and transmitter is not in stop mode.
  • Any transmitter ID is not received from tire pressure warning valve and transmitters.
  • Vehicle speed is more than 40 km/h (25 mph) or no vehicle speed signal is received for 20 minutes or more.

(b) When both conditions below are met:
  • Tire pressure warning valve and transmitter is not in stop mode.
  • No transmitter ID is received from tire pressure warning valve and transmitters for 20 minutes or more.
  • Tire pressure warning valve and transmitter
  • Tire pressure warning ECU and receiver
DTC: 22
C2123 No Signal from Transmitter ID3 Either of the following conditions (a) or (b) is met:
(a) When all conditions below are met:
  • Tire pressure warning valve and transmitter is not in stop mode.
  • Any transmitter ID is not received from tire pressure warning valve and transmitters.
  • Vehicle speed is more than 40 km/h (25 mph) or no vehicle speed signal is received for 20 minutes or more.

(b) When both conditions below are met:
  • Tire pressure warning valve and transmitter is not in stop mode.
  • No transmitter ID is received from tire pressure warning valve and transmitters for 20 minutes or more.
  • Tire pressure warning valve and transmitter
  • Tire pressure warning ECU and receiver
DTC: 23
C2124 No Signal from Transmitter ID4 Either of the following conditions (a) or (b) is met:
(a) When all conditions below are met:
  • Tire pressure warning valve and transmitter is not in stop mode.
  • Any transmitter ID is not received from tire pressure warning valve and transmitters.
  • Vehicle speed is more than 40 km/h (25 mph) or no vehicle speed signal is received for 20 minutes or more.

(b) When both conditions below are met:
  • Tire pressure warning valve and transmitter is not in stop mode.
  • No transmitter ID is received from tire pressure warning valve and transmitters for 20 minutes or more.
  • Tire pressure warning valve and transmitter
  • Tire pressure warning ECU and receiver
DTC: 24
C2125 No Signal from Transmitter ID5 Either of the following conditions (a) or (b) is met:
(a) When all conditions below are met:
  • Tire pressure warning valve and transmitter is not in stop mode.
  • Any transmitter ID is not received from tire pressure warning valve and transmitters.
  • Vehicle speed is more than 40 km/h (25 mph) or no vehicle speed signal is received for 20 minutes or more.

(b) When both conditions below are met:
  • Tire pressure warning valve and transmitter is not in stop mode.
  • No transmitter ID is received from tire pressure warning valve and transmitters for 20 minutes or more.
  • Tire pressure warning valve and transmitter
  • Tire pressure warning ECU and receiver
  • DTC: 25
  • w/ Full Size Spare Tire
C2181 Transmitter ID1 not Received (Test Mode DTC) Test mode procedure is performed.
  • Tire pressure warning valve and transmitter
  • Tire pressure warning ECU and receiver
DTC: 81
C2182 Transmitter ID2 not Received (Test Mode DTC) Test mode procedure is performed.
  • Tire pressure warning valve and transmitter
  • Tire pressure warning ECU and receiver
DTC: 82
C2183 Transmitter ID3 not Received (Test Mode DTC) Test mode procedure is performed.
  • Tire pressure warning valve and transmitter
  • Tire pressure warning ECU and receiver
DTC: 83
C2184 Transmitter ID4 not Received (Test Mode DTC) Test mode procedure is performed.
  • Tire pressure warning valve and transmitter
  • Tire pressure warning ECU and receiver
DTC: 84
C2185 Transmitter ID5 not Received (Test Mode DTC) Test mode procedure is performed.
  • Tire pressure warning valve and transmitter
  • Tire pressure warning ECU and receiver
  • DTC: 85
  • w/ Full Size Spare Tire
NOTE:

When DTCs C2121 to C2124 (C2125: w/ Full Size Spare Tire) are set, DTC C2179 may be set simultaneously. In such cases, troubleshoot DTCs C2121 to C2124 (C2125: w/ Full Size Spare Tire) 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.