DTC U0123: Lost Communication with Yaw Rate Sensor Module; DTC U0124: Lost Communication with Lateral Acceleration Sensor Module: Procedure

1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.
   WARNING:

   Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

   NOTE:

   • w/ Navigation System:

     After the engine switch is turned off, the HDD navigation system requires approximately 6 minutes to record various types of memory and settings. As a result, after turning the engine switch off, wait 6 minutes or more before disconnecting the cable from the negative (-) battery terminal.

   • When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION .

NEXT: Go to next step 

1. Disconnect the E50 yaw rate sensor connector.
   Fig 1: Identifying E50 Yaw Rate Sensor Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   E50-3 (CANH) - E50-2 (CANL)	Engine switch off	54 to 69 Ω

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Yaw Rate Sensor)

NG → REPAIR OR REPLACE YAW RATE SENSOR BRANCH WIRE OR CONNECTOR (CANH, CANL) 

OK: Go to next step 

1. Connect the cable to the negative (-) battery terminal.
   NOTE:

   When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION .

2. Disconnect the E50 yaw rate sensor connector.
   Fig 2: Identifying E50 Yaw Rate Sensor Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   E50-1 (GND) - Body ground	Always	Below 1 Ω

4. Measure the voltage according to the value(s) in table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   E50-4 (IG) - Body ground	Engine switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Yaw Rate Sensor)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   4