Toyota Avalon (XX50) 2019-2022 Service & Repair Manual: Lost Communication With ECM/PCM "A" Missing Message (U010087,U012287,U110487)

DESCRIPTION

The ECM communicates with each sensor and ECU via CAN communication.

If any malfunction is detected in a CAN communication circuit, one or more CAN communication system DTCs are stored.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL
U010087	Lost Communication With ECM/PCM "A" Missing Message	While the vehicle speed is 5 km/h (3 mph) or more and the dynamic radar cruise control system is operating, the ECM continuously receives a communication cut-off signal from the skid control ECU (brake actuator assembly) for approximately 1 second or more.	CAN communication system ECM Skid control ECU (brake actuator assembly)	Does not come on
U012287	Lost Communication with Vehicle Dynamics Control Module Missing Message	When the engine switch is on (IG) and the dynamic radar cruise control system is operating, a communication error between the skid control ECU (brake actuator assembly) and ECM is detected for approximately 2.6 seconds or more.	CAN communication system ECM Skid control ECU (brake actuator assembly)	Does not come on
U110487	Lost Communication with Driving Support ECU Missing Message	While the vehicle speed is 5 km/h (3 mph) or more and the dynamic radar cruise control system is operating, a communication error between the driving support ECU assembly and ECM is detected for 1 second or more.	CAN communication system ECM Driving support ECU assembly	Does not come on

PROCEDURE

1.	CHECK FOR DTCs

(a) Clear the DTCs.

Powertrain > Radar Cruise1 > Clear DTCs

(b) Make sure that the DTC detection conditions are met.

HINT:

If the detection conditions are not met, the system cannot detect the malfunction.

Powertrain > Radar Cruise1 > Trouble Codes

Result	Proceed to
DTC U010087, U012287 and U110487 are not output	A
DTC U010087, U012287 or U110487 is output	B

USE SIMULATION METHOD TO CHECK

GO TO CAN COMMUNICATION SYSTEM

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual > Audio And Visual System(for Gasoline Model): Mute Signal Circuit between Radio Receiver and Stereo Component Amplifier
DESCRIPTION This circuit sends a signal to the stereo component amplifier assembly to mute noise. Because of that, the noise produced by changing the sound source ceases. If there is an open in the circuit, noise can be heard from the speakers when changing the sound source. If there is a short in t ...

Toyota Avalon (XX50) 2019-2022 Owners Manual