DTC U0125: Lost Communication with Yaw Rate Sensor Module; DTC U0126: Lost Communication with Steering Angle Sensor Module; DTC U0129: Lost Communication with Brake System Control Module; DTC U0140: Lost Communication with J/B ECU; DTC U0142: Lost Communication with Body Control Module "B"; DTC U0151: Lost Communication with Airbag ECU; DTC U0235: Lost Communication with Cruise Control Front Distance Range Sensor; DTC U0293: Lost Communication with HV ECU; DTC U1002: Lost Communication with Gateway Module; DTC U1100: Lost Communication with Seat Belt Control ECU; DTC U1104: Lost Communication with Driving Support ECU [10/2014 - 10/2015]: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Turn the Techstream on.
4. Enter the following menus: Body Electrical / Pre-Collision and Pre-Collision 2 / Trouble Codes.
5. Check for DTCs.

   Result

   Result	Proceed to
   DTC U1104 is output	A
   DTC U1104 is not output	B

Result: 

B 

GO TO CAN COMMUNICATION SYSTEM 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2014 - 10/2015] )

Result: 

A 

See step  2

1. Select "CAN Bus Check" from the "System Selection Menu" on the Techstream.
2. Select "Communication Malfunction Check" from the "CAN Bus Check" screen, and then select "OK".

   OK

   CAN communication is normal.

Result: 

NG 

GO TO CAN COMMUNICATION SYSTEM 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2014 - 10/2015] )

Result: 

OK 

See step  3

1. Disconnect the A31 millimeter wave radar sensor assembly connector.
2. Turn the power switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A31-5 (IGB) - Body ground	Power switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Millimeter Wave radar sensor assembly)

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (IGB CIRCUIT) 

Result: 

OK 

See step  4

1. Disconnect the A31 millimeter wave radar sensor assembly connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A31-2 (SGND) - Body ground	Always	Below 1 Ω

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (SGND CIRCUIT) 

Result: 

OK 

See step  5

1. Replace the millimeter wave radar sensor assembly (Refer to REMOVAL [10/2014 - 10/2015] ).
2. Adjust the millimeter wave radar sensor assembly (Refer to ADJUSTMENT [10/2014 - 10/2015] ).

Result: 

NEXT 

See step  6

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Turn the Techstream on.
4. Clear the DTCs (Refer to DTC CHECK / CLEAR [10/2014 - 10/2015] ).
5. Turn the cruise control main switch on.
6. Drive the vehicle at the required speed (45 km/h (28 mph) or higher).
7. Check if the same DTC is output (Refer to DTC CHECK / CLEAR [10/2014 - 10/2015] ).

   Result

   Result	Proceed to
   DTC U1104 is not output	A
   DTC U1104 is output	B

Result: 

A 

END (MILLIMETER WAVE RADAR SENSOR ASSEMBLY WAS DEFECTIVE) 

Result: 

B 

REPLACE DRIVING SUPPORT ECU ASSEMBLY 

(Refer to COMPONENTS [10/2014 - 10/2015] )