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DTC U0073/86: Control Module Communication Bus OFF; DTC U0100/85: Lost Communication with ECM / PCM "A"; DTC U0129/83: Lost Communication with Brake System Control Module: Description

The 4WD control ECU inputs the signals sent from the ECM and skid control ECU 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 No.

DTC Detection 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 seconds.

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 60 km/h (38 mph) or more, communication with the ECM cannot be performed.

Wire harness (CANL, CANH circuit)

4WD control ECU

ECM

U0129/83

When the following continues 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