DTC U0401-81: Invalid Data Received from ECM/PCM "A" Invalid Serial Data Received [08/2020 - ]: Procedure

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CHECK FOR DTCs

Clear the DTCs.
Powertrain > Radar Cruise2 > Clear DTCs
Make sure that the DTC detection conditions are met.
HINT:

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

Check for DTCs.

Powertrain > Radar Cruise2 > Trouble Codes

Result

Result	Proceed to
DTC U0401-81 is not output	A
DTC U0401-81 is output	B

Result:

A

USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [06/2018 - ]

Result:

B

REPLACE ECM

For 2GR-FKS: Refer to COMPONENTS [06/2018 - ]

For A25A-FKS: Refer to COMPONENTS [08/2020 - 08/2021] , or refer to COMPONENTS [08/2021 - ]