DTC U0073/94 Control Module Communication Bus OFF; DTC U0100/65 Lost Communication with ECM / PCM: Description

The translate ECU inputs the signals from the ECM via the CAN communication system.

DTC CHART

DTC No.

DTC Detection Condition

Trouble Area

U0073/94

When using translate ECU to determine malfunction*: Both of following conditions are met:

After translate ECU completes output signal, signal is not sent for 5 seconds or more
Bus off condition occurs one time or more within 100 msec., and this occurs 10 times in a row
When using VSC ECU to determine malfunction*: When IG1 voltage is 0.5 V or more and vehicle speed is 15 km/h (9 mph) or more, signals from malfunctioning translate ECU (as described above) are received continuously for 2 seconds or more

Communication line between engine control ECU and Translate ECU (CAN communication line)

U0100/65

When using translate ECU to determine malfunction*: Both of following conditions are met:

Condition that signals cannot be sent to engine control ECU occurs continuously for 2 seconds or more
Condition that signals cannot be received from engine control ECU occurs continuously for 2 seconds or more
When using VSC ECU to determine malfunction⁽¹⁾: When IG1 voltage is 0.5 V or more and vehicle speed is 15 km/h (9 mph) or more, signals from malfunctioning translate ECU (as described above) are received continuously for 2 seconds or more

Communication line between engine control ECU and Translate ECU (CAN communication line)

HINT:

⁽¹⁾	*: For CAN communication malfunctions, after the malfunction is determined using the translate ECU, the results are sent to the VSC ECU. In total, this takes 7 seconds.

HINT:

This circuit uses the CAN communication. Therefore, if there are any malfunctions in the communication circuit, one or more DTCs in the CAN communication system will be output.

RECONFIRM DTC

Clear the DTC.
Start the engine.
Drive the vehicle at a speed of 15 km/h (9 mph) and turn the steering wheel to the right and left.
Check that no CAN communication system DTC is output.
If ABS and VSC DTCs are output, record them.

Result:

RESULT REFERENCE

Result	Proceed to
DTC is output for the CAN communication system	A (HOW TO PROCEED WITH TROUBLESHOOTING )
DTC is output (ABS and VSC DTCs are output)	B
DTC is not output	C

B : REPAIR CIRCUIT INDICATED BY OUTPUT CODE

C : END

A : Go to CAN COMMUNICATION SYSTEM