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DTC U0073/86 Control Module Communication Bus OFF; DTC U0100/85 Lost Communication With ECM / PCM "A"; DTC U0122/83 Lost Communication With Vehicle Dynamics Control Module; DTC U0126/84 Lost Communication With Steering Angle Sensor Module;: Description

WARNING: This page is about a different car, the 2006 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.

The 4WD control ECU inputs the signals sent from the ECM, skid control ECU, and steering angle sensor via the CAN communication system.
When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.

DTC U0073/86 DETECTION CONDITION - TROUBLE AREA

DTC No.	DTC Detecting Condition	Trouble Area
U0073/86	When the following continues for 5 seconds or more: Signals from the 4WD control ECU are not received. When the following occurs 10 times consecutively: A communication malfunction (bus off) occurs one or more times within 0.1 second.	Wire harness (CANL, CANH circuit) 4WD control ECU
U0100/85	When both of the following continue for 2 seconds or more: The voltage of the IG1 terminal is 10 V or more. At a vehicle speed of 38 mph (60 km/h) or more, communication with the ECM cannot be performed.	Wire harness (CANL, CANH circuit) 4WD control ECU ECM
U0122/83	When both of the following continue for 3 seconds or more: The voltage of the IG1 terminal is 10 V or more. Communication with the skid control ECU cannot be performed.	Wire harness (CANL, CANH circuit) 4WD control ECU Skid control ECU
U0126/84	When both of the following continue for 1 second or more: The voltage of the IG1 terminal is 10 V or more. Communication with the steering angle sensor cannot be performed. When all of the following occur 10 times consecutively: The voltage of the IG1 terminal is 10 V or more. The vehicle speed is 38 mph (60 km/h) or more. The condition that communication with the steering angle sensor cannot be performed occurs once within 5 seconds.	Wire harness (CANL, CANH circuit) 4WD control ECU Steering angle sensor

CHECK DTC
1. Check DTC (See DTC CHECK / CLEAR ).
2. Record the output DTC (4WD control system).
  HINT:
  
  When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.
NEXT : GO TO CAN COMMUNICATION SYSTEM