DTC U0122: Lost Communication with Vehicle Dynamics Control Module; DTC U0123: Lost Communication with Yaw Rate Sensor Module; DTC U0126: Lost Communication with Steering Angle Sensor Module; DTC U0293: Lost Communication with HV ECU; DTC U1104: Lost Communication with Driving Support ECU: 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: Powertrain / Radar Cruise / Trouble Codes.
5. Read the DTCs.

   Result

   Result	Proceed to
   DTC U1104 is output	A
   DTCs other than U1104 are output	B

B → See step   6 

A: Go to next step 

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

   OK

   Communication system is normal.

NG → See step   6 

OK: Go to next step 

1. Disconnect the driving support ECU connector.
   Fig 1: View Of Wire Harness Connector To Driving Support ECU

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

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   L60-25 (GND) - Body ground	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Driving Support ECU)

3. Reconnect the driving support ECU connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (DRIVING SUPPORT ECU - BODY GROUND) 

OK: Go to next step 

1. Replace the driving support control ECU. Refer to REMOVAL .

NEXT: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Clear the DTCs. Refer to DTC CHECK / CLEAR .
4. Perform the following to make sure that the DTC detection conditions are met.

   HINT: 

   If the detection conditions are not met, the malfunction cannot be detected.

   1. Drive the vehicle at a speed for which cruise control operation is possible.
   2. Turn the cruise control main switch on.
   3. Push the -SET switch to activate the cruise control.
5. Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.
6. Read the DTCs.

   Result

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

B → See step   7 

A → END