Toyota Avalon (XX50) 2019-2022 Service & Repair Manual: Driving Support ECU Communication Abnormal (C1A52)

DESCRIPTION

The DTC C1A52 is stored when the ECM cannot recognize the driving support ECU assembly.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL
C1A52	Driving Support ECU Communication Abnormal	Approximately 17 seconds after the engine switch is turned on (IG), the ECM cannot recognize the driving support ECU assembly for approximately 1.3 seconds or more.	ECM	Does not come on

CAUTION / NOTICE / HINT

NOTICE:

Before replacing the ECM, refer to Registration.

Click here

PROCEDURE

1.	CHECK FOR DTCs

(a) Clear the DTCs.

Powertrain > Radar Cruise2 > 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 Cruise2 > Trouble Codes

Result	Proceed to
DTC C1A52 is not output	A
DTC C1A52 is output	B

USE SIMULATION METHOD TO CHECK

REPLACE ECM

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual > Smart Key System(for Start Function, Gasoline Model): Ignition Hold Monitor Malfunction (B2271)
DESCRIPTION This DTC is stored when a malfunction in the IG circuit or IG hold circuit of the certification ECU (smart key ECU assembly) is detected. DTC No. Detection Item DTC Detection Condition Trouble Area Note B2271 Ignition Hold Monitor Malfunction When either of the following conditions is me ...

Toyota Avalon (XX50) 2019-2022 Owners Manual