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DTC U0100 Lost Communication with ECM/PCM "A"; DTC U0129 Lost Communication with Brake System Control Module; DTC U0130 Lost Communication with Steering Effort Control Module; DTC U1104 Lost Communication with Driving Support ECU; DTC U1105 Lost Communication with Parking Assist ECU: Description

The power steering ECU inputs and outputs driving support ECU, parking assist ECU, ECM, skid control ECU, and steering control ECU signals via CAN communication.

DTC DETECTION CONDITION CHART

DTC No.	DTC Detection Condition	Trouble Area
U0100	ECM communication error	CAN communication system ECM (when only U0105 is output)
U0129	Skid control ECU communication error	CAN communication system Skid control ECU (when only U0129 is output)
U0130	VGRS control ECU communication error	CAN communication system VGRS control ECU (when only U0130 is output)
U1104	Driving support ECU communication error	CAN communication system Driving support ECU (when only U1104 is output)
U01105	Parking assist ECU communication error	CAN communication system Parking assist ECU (when only U1105 is output)

HINT:

When 2 or more DTCs starting with "U" are output simultaneously, inspect the connectors and wire harness of each ECU.
If the power steering ECU detects DTC U0129 only, it adjusts the amount of power assistance for a speed of 100 km/h (62 mph) and continues system control.